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I am working on a side project in VB, it is a network monitoring tool to pings a number of devices which should come back as successful or failed. I have extreme limits in programming so forgive me.
I am using buttons, a total of 34 for each device that I want to ping that returns a success or fail which will color code green(success) and red(failed) but I am sure there is a better way? Right now, my code is stuck on one button, I cant figure out how to step to the next one on the list. In my code, I have it commented out of the results I want produced which is where I am stuck on.
The text file contains all my IP addresses I want to ping separated by a comma.
Basically, when the form is running, it will display each button as green or red, depending on if the device is online or not. I want the code to loop every 2 minutes as well to keep the devices up to date. Literally a device monitoring tool. I was able to get it to work using 34 different End If statements but that is messy and a lot of work to maintain. Any assistance would be helpful.
Using MyReader As New Microsoft.VisualBasic.FileIO.TextFieldParser("\\txt file location\device.txt")
MyReader.TextFieldType = FileIO.FieldType.Delimited
MyReader.SetDelimiters(",")
Dim currentRow As String()
Dim MyLen() As String = {"Button1", "Button2", "Button3", "Button4", "Button5", "Button6", "Button7", "Button8", "Button9", "Button10", "Button11", "Button12", "Button13", "Button14", "Button15", "Button16", "Button17", "Button18", "Button19", "Button20", "Button21", "Button22", "Button23", "Button24", "Button25", "Button26", "Button27", "Button28", "Button29", "Button30", "Button31", "Button32", "Button33", "Button34"}
While Not MyReader.EndOfData
Try
currentRow = MyReader.ReadFields()
Dim currentField As String
For Each currentField In currentRow
If My.Computer.Network.Ping(currentField) Then
MsgBox(MyLen)
'MyLen = Color.LimeGreen
Else
MsgBox(MyLen)
'MyLen.Text = "Failed"
'MyLen.BackColor = Color.Red
End If
Next
Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
MsgBox("Line " & ex.Message & "is not valid and will be skipped.")
End Try
End While
End Using
enter image description here
Here is some code that takes a different approach. To try it create a new Form app with only a FlowLayoutPanel and Timer on it. Use the default names. It might be above your skill level but using the debugger you might learn something. Or not.
Public Class Form1
Private MyButtons As New List(Of Button)
Private Sub Form1_Shown(sender As Object, e As EventArgs) Handles Me.Shown
Timer1.Enabled = False 'started later
Timer1.Interval = CInt(TimeSpan.FromMinutes(2).TotalMilliseconds) '<<<< Change >>>>
Dim path As String = "\\txt file location\device.txt"
Dim text As String = IO.File.ReadAllText(path) 'use this
''for testing >>>>>
'Dim text As String = "10.88.0.70, 10.88.0.122,192.168.0.15, 10.88.0.254, 1.2.3.4" ''for testing
''for testing <<<<<
Dim spltCHs() As Char = {","c, " "c, ControlChars.Tab, ControlChars.Cr, ControlChars.Lf}
Dim IPs() As String = text.Split(spltCHs, StringSplitOptions.RemoveEmptyEntries)
For Each addr As String In IPs
Dim b As New Button
Dim p As New MyPinger(addr)
p.MyButton = b
b.Tag = p 'set tag to the MyPinger for this address
b.AutoSize = True
b.Font = New Font("Lucida Console", 10, FontStyle.Bold)
b.BackColor = Drawing.Color.LightSkyBlue
'center text in button
Dim lAddr As String = p.Address
Dim t As String = New String(" "c, (16 - lAddr.Length) \ 2)
Dim txt As String = t & lAddr & t
b.Text = txt.PadRight(16, " "c)
b.Name = "btn" & lAddr.Replace("."c, "_"c)
AddHandler b.Click, AddressOf SomeButton_Click 'handler for button
MyButtons.Add(b) 'add button to list
Next
'sort by IP
MyButtons = (From b In MyButtons
Select b Order By DirectCast(b.Tag, MyPinger).Address(True)).ToList
For Each b As Button In MyButtons
FlowLayoutPanel1.Controls.Add(b) 'add button to panel
Next
FlowLayoutPanel1.Anchor = AnchorStyles.Bottom Or AnchorStyles.Left Or AnchorStyles.Right Or AnchorStyles.Top
Timer1.Enabled = True 'start the timer
End Sub
Private Sub SomeButton_Click(sender As Object, e As EventArgs)
'if button clicked ping it
Dim b As Button = DirectCast(sender, Button) 'which button
b.BackColor = MyPinger.UnknownColor
Dim myP As MyPinger = DirectCast(b.Tag, MyPinger) ''get the MyPinger for this
myP.DoPing() 'do the ping
End Sub
Private Async Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
Timer1.Enabled = False
Dim myPs As New List(Of MyPinger)
For Each b As Button In MyButtons
b.BackColor = MyPinger.UnknownColor
Dim myP As MyPinger = DirectCast(b.Tag, MyPinger)
myPs.Add(myP)
Next
Dim t As Task
t = Task.Run(Sub()
Threading.Thread.Sleep(25)
For Each myP As MyPinger In myPs
myP.DoPing()
Next
End Sub)
Await t
Timer1.Enabled = True
End Sub
End Class
Public Class MyPinger
Public Shared ReadOnly UpColor As Drawing.Color = Drawing.Color.LightGreen
Public Shared ReadOnly DownColor As Drawing.Color = Drawing.Color.Red
Public Shared ReadOnly UnknownColor As Drawing.Color = Drawing.Color.Yellow
Private _ip As Net.IPAddress
Private _ping As Net.NetworkInformation.Ping
Public LastReply As Net.NetworkInformation.PingReply
Private Shared ReadOnly PingTMO As Integer = 2500
Private _waiter As New Threading.AutoResetEvent(True)
Public MyButton As Button
Public Sub New(IPAddr As String)
Me._ip = Net.IPAddress.Parse(IPAddr) 'will throw exception if IP invalid <<<<<
Me._ping = New Net.NetworkInformation.Ping 'create the ping
'do initial ping
Dim t As Task = Task.Run(Sub()
Threading.Thread.Sleep(25) 'so init has time
Me.DoPingAsync()
End Sub)
End Sub
Private Async Sub DoPingAsync()
If Me._waiter.WaitOne(0) Then 'only one at a time for this IP
Me.LastReply = Await Me._ping.SendPingAsync(Me._ip, PingTMO)
Dim c As Drawing.Color
Select Case Me.LastReply.Status
Case Net.NetworkInformation.IPStatus.Success
c = UpColor
Case Else
c = DownColor
End Select
Me.SetButColor(c)
Me._waiter.Set()
End If
End Sub
Public Sub DoPing()
Me.DoPingAsync()
End Sub
Private Sub SetButColor(c As Drawing.Color)
If Me.MyButton IsNot Nothing Then
If Me.MyButton.InvokeRequired Then
Me.MyButton.BeginInvoke(Sub()
Me.SetButColor(c)
End Sub)
Else
Me.MyButton.BackColor = c
End If
End If
End Sub
Public Function TheIP() As Net.IPAddress
Return Me._ip
End Function
Public Function Address(Optional LeadingZeros As Boolean = False) As String
Dim rv As String = ""
If LeadingZeros Then
Dim byts() As Byte = Me._ip.GetAddressBytes
For Each b As Byte In byts
rv &= b.ToString.PadLeft(3, "0"c)
rv &= "."
Next
Else
rv = Me._ip.ToString
End If
Return rv.Trim("."c)
End Function
End Class
I tried to receive data from medical 'Mindray bs 200' device through serial port. data received but is unreadable. Unable to find the kind of data encryption.
Here is the code that receives the data
Private Sub comPort_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles comPort.DataReceived
Dim str As String = ""
If e.EventType = SerialData.Chars Then
Do
Dim bytecount As Integer = comPort.BytesToRead
If bytecount = 0 Then
Exit Do
End If
Dim byteBuffer(bytecount) As Byte
comPort.Encoding = Encoding.GetEncoding(28591)
' comPort.Encoding = Encoding.GetEncoding(1252)
'comPort.Encoding = Encoding.GetEncoding("Windows-1252")
comPort.Read(byteBuffer, 0, bytecount)
str = str & System.Text.Encoding.ASCII.GetString(byteBuffer, 0, 1)
' The str looks like
Loop
End If
RaiseEvent ScanDataRecieved(str)
End Sub
Here is the data received
??????????????????????????????????????????????????????????????????????????????????????????????????????????????????X???????????????????
While not for this particular device, this document discusses a device that uses the same RS232 communication protocol and recommends the following SerialPort settings:
Baud rate: 115200
DataBits: 8
StopBits: 1
Parity: None
No flow control
Note: Minimum baud rate is 57600.
According to this document
2.1 Message Grammar:
Each HL7 message is composed of segments that end with <CR>
3 Communication Process and Message Example:
A message of HL7 protocol is the format of: <SB> ddddd <EB><CR>
ASCII value (HEX)
<SB> (start of message): 0B (VT - vertical tab)
<EB> (end of message): 1C (FS - file separator)
<CR> (carriage return) 0D (carriage return)
In the code below, I'll show how to use a buffer to collect data when "start of message" is received (HEX: 0B) and fill the buffer until "end of message" (HEX: 1C) followed by a carriage return (HEX: 0D) is received - at which point we'll raise an event and/or output the data.
For testing, we'll also write the data to a file in the Documents folder - this file is deleted each time the program starts so that only data from the current execution of the program is contained in the file. Each byte of data is output as a 2-digit hexadecimal value which allows us to see if a value is a control character.
The following may be helpful for interpreting the values:
ASCII Table
ASCII Code - The extended ASCII table
Create a class (name: HelperSerialPort.vb)
HelperSerialPort.vb
Note: The code in method Port_DataReceived (within the if-elseif statements) is untested - I don't have the particular device that you're using to be able to test it.
'(.NET Framework) - Add reference: Project => Add Reference => Assemblies => System.Management
'add using statement: Using System.Management;
'
'For >= .NET 5, install NuGet Package: System.IO.Ports and System.Management
'add Imports statements: Imports System.IO.Ports; Imports System.Management;
'
'
Imports System.Management
Imports System.IO.Ports
'specify valid baud rates
Public Enum PortBaudRate As Integer
Baud57600 = 57600
Baud76800 = 76800
Baud115200 = 115200
End Enum
Public Class HelperSerialPort
Implements IDisposable
Private Const BufferSize As Integer = 4096 'this value may need to be changed
Private Port As SerialPort = Nothing
Private BytesReadMessage As Integer = 0 'used to hold message bytes read
Private Buffer(BufferSize) As Byte 'used to hold data
Private Filename As String = Nothing
Private IsMessage As Boolean = False
'events that can be subscribed to
Public Event DataReceived(ByVal sender As Object, ByVal data As String)
Public Event ErrorReceived(ByVal sender As Object, ByVal errMsg As String)
Sub New()
'set value
'data will be written to this file for testing
Filename = System.IO.Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), "Mindray BS200.txt")
If Not String.IsNullOrEmpty(Filename) AndAlso System.IO.File.Exists(Filename) Then
'delete existing file
System.IO.File.Delete(Filename)
End If
System.Diagnostics.Debug.WriteLine("Filename: '" & Filename & "'")
End Sub
Public Function Connect(ByVal comPort As String, ByVal Optional baudRate As PortBaudRate = PortBaudRate.Baud115200) As String
Dim errMsg As String = String.Empty
Dim portName As String = String.Empty
Dim result As String = String.Empty
If String.IsNullOrEmpty(comPort) Then
errMsg = "COM port not selected"
Throw New Exception(errMsg)
End If
Try
If Port Is Nothing Then
'create new instance
Port = New SerialPort(comPort)
'subscribe to events (add event handlers)
AddHandler Port.DataReceived, AddressOf Port_DataReceived
AddHandler Port.ErrorReceived, AddressOf Port_ErrorReceived
End If
If Not Port.IsOpen Then
'set properties
Port.BaudRate = baudRate
Port.Handshake = Handshake.None
'if parity is even or odd, then set DataBits = 7
'if parity is none, set DataBits = 8
Port.Parity = Parity.None
Port.DataBits = 8
Port.StopBits = StopBits.One
'Port.ReadTimeout = 500 'this value may need to be adjusted
Port.WriteTimeout = 500 'this value may need to be adjusted
Port.DtrEnable = True 'enable Data Terminal Ready
'Port.RtsEnable = True 'enable Request to Send
'Port.DiscardNull = True
'Port.ReceivedBytesThreshold = 1 'number of bytes that causes 'DataReceived' event to be raised; default is 1
'open port
Port.Open()
result = "Status: Connected"
Else
result = "Status: Already Connected"
End If
Catch ex As System.IO.IOException
errMsg = "Error: " & ex.Message
result = errMsg 'set value
Debug.WriteLine(errMsg)
Dispose()
Catch ex As Exception
errMsg = "Error: " & ex.Message
result = errMsg 'set value
Debug.WriteLine(errMsg)
Throw ex
End Try
Debug.WriteLine(result)
Return result
End Function
Public Function Disconnect() As String
Dispose()
Return "Status: Disconnected"
End Function
Public Sub Dispose() Implements System.IDisposable.Dispose
If Port IsNot Nothing Then
'unsubscribe from events (remove event handlers)
RemoveHandler Port.DataReceived, AddressOf Port_DataReceived
RemoveHandler Port.ErrorReceived, AddressOf Port_ErrorReceived
Port.Dispose()
Port = Nothing
Else
Debug.WriteLine("Info: Port is null")
End If
End Sub
Public Function IsPortOpen() As Boolean
If Port IsNot Nothing Then
If Port.IsOpen Then
Return True
Else
Try
Port.Dispose()
Catch ex As Exception
'do nothing
Debug.WriteLine("Error (IsPortOpen): " & ex.Message)
End Try
End If
Port = Nothing
System.GC.Collect()
System.GC.Collect()
End If
Return False
End Function
Private Sub Port_DataReceived(ByVal sender As Object, ByVal e As SerialDataReceivedEventArgs)
'ToDo: add desired code
Dim bytesRead As Integer = 0
Dim bytesToRead As Integer = 1
Dim errMsg As String = String.Empty
'read SerialPort data
Do
'read 1 byte at a time
bytesRead = Port.Read(Buffer, BytesReadMessage, bytesToRead)
'when <SB> (HEX: 0B) is received, remove all existing data from buffer
'this will result in the buffer only containing our desired data.
'when <EB> (HEX: 1C) is received followed by <CR> (HEX: 0D),
'this is the end of the message, so we'll send the message and/or display it.
'Buffer(BytesReadMessage) contains the last byte of data that was read
'
If Buffer(BytesReadMessage) = &HB Then
'0x0B - VT (vertical tab); in the documentation this is '<SB>' - start of message
System.Diagnostics.Debug.WriteLine("<SB> (start of message)")
'remove existing data (get ready for new message)
Array.Clear(Buffer, 0, Buffer.Length)
're-initialize to -1. It's incremented below which will result in the value being 0
BytesReadMessage = -1
'set value - start saving data to the buffer
IsMessage = True
ElseIf IsMessage AndAlso Buffer(BytesReadMessage) = &HD AndAlso Buffer(BytesReadMessage - 1) = &H1C Then
'0x1C - FS (file separator); in the documentation this is '<EB>' - end of message
'0x0D - CR (carriage return); in the documentation this is '<CR>'
System.Diagnostics.Debug.WriteLine("<EB> (end of message)")
'raise event to send data
SendData(Buffer)
'set value - stop saving data to the buffer
IsMessage = False
ElseIf Not IsMessage Then
'for debugging/testing, display non-message data
System.Diagnostics.Debug.WriteLine("Non-message data: " & Buffer(BytesReadMessage).ToString("X2"))
End If
'set value
BytesReadMessage += bytesRead
Debug.WriteLine("Info: BytesReadMessage: " & BytesReadMessage.ToString() & " bytesRead: " & bytesRead.ToString() & " Port.BytesToRead: " & Port.BytesToRead.ToString())
Loop While (Port.BytesToRead > 0)
Debug.WriteLine(String.Format("{0}---------------------------{0}", System.Environment.NewLine))
End Sub
Private Sub Port_ErrorReceived(ByVal sender As Object, ByVal e As SerialErrorReceivedEventArgs)
'ToDo: add desired code
Dim errMsg As String = e.EventType.ToString()
Debug.WriteLine("Port_ErrorReceived: " & errMsg)
'raise event
RaiseEvent ErrorReceived(Me, errMsg)
End Sub
Public Sub SendData(buffer() As Byte)
'ToDo: modify the code below and/or add desired code
'convert to a string that's human-readable
Dim data As String = String.Empty
If buffer IsNot Nothing Then
For i As Integer = 0 To BytesReadMessage Step 1
If Not String.IsNullOrEmpty(data) Then
data += " " 'append space
End If
'for testing, convert to a 2-digit HEX value
data += buffer(i).ToString("X2")
Next
'add newline
data += System.Environment.NewLine
End If
System.Diagnostics.Debug.WriteLine("data: " & data)
'for testing save to file
If Not String.IsNullOrEmpty(Filename) Then
'append data to file
System.IO.File.AppendAllText(Filename, data)
End If
'raise event
RaiseEvent DataReceived(Me, data)
'Note: "When receiving the message, the LIS (Laboratory Information Management System) host first judges the legality and type of the message and then replies accordingly."
'ToDo: A response needs to be sent for each message received (see documentation for information on how to create the appropriate message - "3 Communication Process and Message Example")
End Sub
Public Sub WriteToSerialPort(ByVal data As String)
Dim errMsg As String = String.Empty
Try
If Port.IsOpen Then
'convert string to Byte array
Dim hexArr As Byte() = System.Text.Encoding.ASCII.GetBytes(data)
For Each hexVal As Byte In hexArr
'convert byte to byte array
Dim tempArr As Byte() = New Byte() {hexVal}
'write
Port.Write(tempArr, 0, 1)
'add 1 ms delay before writing next byte
System.Threading.Thread.Sleep(1)
Next
Else
errMsg = "Error: Port is not open. Please open the connection and try again."
Debug.WriteLine(errMsg)
Throw New Exception(errMsg)
End If
Catch ex As Exception
errMsg = "Error: " & ex.Message
Debug.WriteLine(errMsg)
Throw ex
End Try
End Sub
End Class
Below is an alternative version of method Port_DataReceived that uses ReadExisting() instead - however, it may not work in your situation.
Port_DataReceived (version that uses ReadExisting):
Private Sub Port_DataReceived(ByVal sender As Object, ByVal e As SerialDataReceivedEventArgs)
'ToDo: add desired code
'read SerialPort data
Dim data As String = String.Empty
data = Port.ReadExisting()
'data = Port.ReadLine
Debug.WriteLine("Port_DataReceived: " & data)
'raise event
RaiseEvent DataReceived(Me, data)
End Sub
Form1:
Add a Button (name: btnConnectDisconnect)
Double-click the button to add the event handler
Add a RichTextBox (name: RichTextBox1)
Form1.vb
Note: In the code below, you'll need to update helper.Connect("COM1") with the correct COM port.
Public Class Form1
Private helper As HelperSerialPort = New HelperSerialPort()
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
End Sub
Private Sub Disconnect()
If helper IsNot Nothing Then
'unsubscribe from event(s)
RemoveHandler helper.DataReceived, AddressOf Helper_DataReceived
RemoveHandler helper.ErrorReceived, AddressOf Helper_ErrorReceived
helper.Dispose()
helper = Nothing
End If
End Sub
Private Sub btnConnectDisconnect_Click(sender As Object, e As EventArgs) Handles btnConnectDisconnect.Click
If helper Is Nothing Then
'create new instance
helper = New HelperSerialPort()
End If
If btnConnectDisconnect.Text = "Connect" Then
'clear existing data
RichTextBox1.Clear()
'ToDo: change to your desired COM port
helper.Connect("COM1")
'subscribe to event(s)
AddHandler helper.DataReceived, AddressOf Helper_DataReceived
AddHandler helper.ErrorReceived, AddressOf Helper_ErrorReceived
'set text
btnConnectDisconnect.Text = "Disconnect"
btnConnectDisconnect.Refresh()
Else
Disconnect()
'set text
btnConnectDisconnect.Text = "Connect"
btnConnectDisconnect.Refresh()
End If
End Sub
Private Sub Helper_DataReceived(ByVal sender As Object, ByVal data As String)
'ToDo: add desired code
System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString("HH:mm:ss") & " - Helper_DataReceived: " & data)
'append data to RichTextBox
RichTextBox1.Invoke(New MethodInvoker(Sub()
RichTextBox1.AppendText(DateTime.Now.ToString("yyyy/MM/dd HH:mm:ss.fff") & " - " & data)
End Sub))
End Sub
Private Sub Helper_ErrorReceived(ByVal sender As Object, ByVal errMsg As String)
'ToDo: add desired code
System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString("HH:mm:ss") & " - Helper_ErrorReceived: " & errMsg)
'append error message to RichTextBox
RichTextBox1.Invoke(New MethodInvoker(Sub()
RichTextBox1.AppendText(errMsg)
End Sub))
End Sub
Private Sub Form1_FormClosed(sender As Object, e As FormClosedEventArgs) Handles MyBase.FormClosed
Disconnect()
End Sub
End Class
Resources:
Host Interface Manual
HL7 Version 2.3.1
Modem control signals
I have a school bell project coded with Visual Basic 2010 Express. The computer which runs my program has two or more sound cards. First I will list the sound cards to user. User will select the sound card to work. Finally my program will ring the bells on that sound card. Everything is okey for my codes but i can't list the names of sound cards and ring the bell on specified sound card.
I use WMPLib to play music. I have these codes but there becomes an error "the value is not in the expected range". I spotted where the error is in my codes:
Public Declare Function waveOutGetNumDevs Lib "winmm" () As Integer
Public Declare Function mciSendCommand Lib "winmm.dll" Alias "mciSendCommandA" (ByVal wDeviceID As Integer, ByVal uMessage As String, ByVal dwParam1 As Integer, ByVal dwParam2 As Object) As Integer
Public Declare Function mciGetErrorString Lib "winmm.dll" Alias "mciGetErrorStringA" (ByVal dwError As Integer, ByVal lpstrBuffer As String, ByVal uLength As Integer) As Integer
Public Declare Function mciSendString Lib "winmm.dll" Alias "mciSendStringA" (ByVal lpstrCommand As String, ByVal lpstrReturnString As String, ByVal uReturnLength As Integer, ByVal hwndCallback As Integer) As Integer
Public Declare Function mciGetDeviceID Lib "winmm.dll" Alias "mciGetDeviceIDA" (ByVal lpstrName As String) As Integer
Public Const MMSYSERR_NOERROR = 0
Public Const MCI_SET = &H80D
Public Const MCI_WAVE_OUTPUT = &H800000
Public Structure MCI_WAVE_SET_PARMS
Dim dwCallback As Integer
Dim dwTimeFormat As Integer
Dim dwAudio As Integer
Dim wInput As Integer
Dim wOutput As Integer
Dim wFormatTag As Short
Dim wReserved2 As Short
Dim nChannels As Short
Dim wReserved3 As Short
Dim nSamplesPerSec As Integer
Dim nAvgBytesPerSec As Integer
Dim nBlockAlign As Short
Dim wReserved4 As Short
Dim wBitsPerSample As Short
Dim wReserved5 As Short
End Structure
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Dim parms As MCI_WAVE_SET_PARMS
Dim wDeviceID As Integer
Dim ret As Integer
parms.wOutput = 0
wDeviceID = mciGetDeviceID("waveaudio")
' the value is not in the expected range error is here and it spots parms
ret = mciSendCommand(wDeviceID, MCI_SET, MCI_WAVE_OUTPUT, parms)
If (ret <> MMSYSERR_NOERROR) Then
Stop
End If
If ofd.ShowDialog Then
ret = mciSendString("Open " & Chr(34) & ofd.FileName & Chr(34) & " alias audio", CStr(0), 0, 0)
ret = mciSendString("Open audio", CStr(0), 0, 0)
End If
End Sub
WindowsMedia.Net
You can do this using WindowsMedia.Net library.
The following example is taken from the link below, it is a code blonging to a Windows form and contains the functionality needed to list all available audio devices and choose the default device (the one that will act as sound output).
Set default Wave Out Audio Device - VB.Net / DRVM_MAPPER_PREFERRED_SET
First i will try to split the code into 2 parts:
List available audio devices
Change default audio device
List available devices
Private Sub RefreshInformation()
PopulateDeviceComboBox()
DisplayDefaultWaveOutDevice()
End Sub
Private Sub PopulateDeviceComboBox()
DevicesComboBox.Items.Clear()
' How many wave out devices are there? WaveOutGetNumDevs API call.
Dim waveOutDeviceCount As Integer = waveOut.GetNumDevs()
For i As Integer = 0 To waveOutDeviceCount - 1
Dim caps As New WaveOutCaps
' Get a name - its in a WAVEOUTCAPS structure.
' The name is truncated to 31 chars by the api call. You probably have to
' dig around in the registry to get the full name.
Dim result As Integer = waveOut.GetDevCaps(i, caps, Marshal.SizeOf(caps))
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("GetDevCaps() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
DevicesComboBox.Items.Add(New WaveOutDevice(i, caps))
Next
DevicesComboBox.SelectedIndex = 0
End Sub
Private Sub DisplayDefaultWaveOutDevice()
Dim currentDefault As Integer = GetIdOfDefaultWaveOutDevice()
Dim device As WaveOutDevice = DirectCast(DevicesComboBox.Items(currentDefault), WaveOutDevice)
DefaultDeviceLabel.Text = "Defualt: " & device.WaveOutCaps.szPname
End Sub
Private Function GetIdOfDefaultWaveOutDevice() As Integer
Dim id As Integer = 0
Dim hId As IntPtr
Dim flags As Integer = 0
Dim hFlags As IntPtr
Dim result As Integer
Try
' It would be easier to declare a nice overload with ByRef Integers.
hId = Marshal.AllocHGlobal(4)
hFlags = Marshal.AllocHGlobal(4)
' http://msdn.microsoft.com/en-us/library/bb981557.aspx
result = waveOut.Message(WAVE_MAPPER, DRVM_MAPPER_PREFERRED_GET, hId, hFlags)
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("waveOutMessage() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
id = Marshal.ReadInt32(hId)
flags = Marshal.ReadInt32(hFlags)
Finally
Marshal.FreeHGlobal(hId)
Marshal.FreeHGlobal(hFlags)
End Try
' There is only one flag, DRVM_MAPPER_PREFERRED_FLAGS_PREFERREDONLY, defined as 1
' "When the DRVM_MAPPER_PREFERRED_FLAGS_PREFERREDONLY flag bit is set, ... blah ...,
' the waveIn and waveOut APIs use only the current preferred device and do not search
' for other available devices if the preferred device is unavailable.
Return id
End Function
Change default device
Private Sub SetDefaultButton_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles SetDefaultButton.Click
If DevicesComboBox.Items.Count = 0 Then Return
Dim selectedDevice As WaveOutDevice = DirectCast(DevicesComboBox.SelectedItem, WaveOutDevice)
SetDefault(selectedDevice.Id)
RefreshInformation()
End Sub
Private Sub SetDefault(ByVal id As Integer)
Dim defaultId As Integer = GetIdOfDefaultWaveOutDevice()
If defaultId = id Then Return ' no change.
Dim result As Integer
' So here we say "change the Id of the device that has id id to 0", which makes it the default.
result = waveOut.Message(WAVE_MAPPER, DRVM_MAPPER_PREFERRED_SET, New IntPtr(id), IntPtr.Zero)
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("waveOutMessage() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
End Sub
Full code
Imports MultiMedia
Imports System.Runtime.InteropServices
Imports System.ComponentModel
Public Class Form1
Private DevicesComboBox As New ComboBox
Private DefaultDeviceLabel As New Label
Private WithEvents SetDefaultButton As New Button
Private Const DRVM_MAPPER_PREFERRED_GET As Integer = &H2015
Private Const DRVM_MAPPER_PREFERRED_SET As Integer = &H2016
Private WAVE_MAPPER As New IntPtr(-1)
' This just brings together a device ID and a WaveOutCaps so
' that we can store them in a combobox.
Private Structure WaveOutDevice
Private m_id As Integer
Public Property Id() As Integer
Get
Return m_id
End Get
Set(ByVal value As Integer)
m_id = value
End Set
End Property
Private m_caps As WaveOutCaps
Public Property WaveOutCaps() As WaveOutCaps
Get
Return m_caps
End Get
Set(ByVal value As WaveOutCaps)
m_caps = value
End Set
End Property
Sub New(ByVal id As Integer, ByVal caps As WaveOutCaps)
m_id = id
m_caps = caps
End Sub
Public Overrides Function ToString() As String
Return WaveOutCaps.szPname
End Function
End Structure
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
' I do use the IDE for this stuff normally... (in case anyone is wondering)
Me.Controls.AddRange(New Control() {DevicesComboBox, DefaultDeviceLabel, SetDefaultButton})
DevicesComboBox.Location = New Point(5, 5)
DevicesComboBox.DropDownStyle = ComboBoxStyle.DropDownList
DevicesComboBox.Width = Me.ClientSize.Width - 10
DevicesComboBox.Anchor = AnchorStyles.Left Or AnchorStyles.Right
DefaultDeviceLabel.Location = New Point(DevicesComboBox.Left, DevicesComboBox.Bottom + 5)
DefaultDeviceLabel.AutoSize = True
SetDefaultButton.Location = New Point(DefaultDeviceLabel.Left, DefaultDeviceLabel.Bottom + 5)
SetDefaultButton.Text = "Set Default"
SetDefaultButton.AutoSize = True
RefreshInformation()
End Sub
Private Sub RefreshInformation()
PopulateDeviceComboBox()
DisplayDefaultWaveOutDevice()
End Sub
Private Sub PopulateDeviceComboBox()
DevicesComboBox.Items.Clear()
' How many wave out devices are there? WaveOutGetNumDevs API call.
Dim waveOutDeviceCount As Integer = waveOut.GetNumDevs()
For i As Integer = 0 To waveOutDeviceCount - 1
Dim caps As New WaveOutCaps
' Get a name - its in a WAVEOUTCAPS structure.
' The name is truncated to 31 chars by the api call. You probably have to
' dig around in the registry to get the full name.
Dim result As Integer = waveOut.GetDevCaps(i, caps, Marshal.SizeOf(caps))
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("GetDevCaps() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
DevicesComboBox.Items.Add(New WaveOutDevice(i, caps))
Next
DevicesComboBox.SelectedIndex = 0
End Sub
Private Sub DisplayDefaultWaveOutDevice()
Dim currentDefault As Integer = GetIdOfDefaultWaveOutDevice()
Dim device As WaveOutDevice = DirectCast(DevicesComboBox.Items(currentDefault), WaveOutDevice)
DefaultDeviceLabel.Text = "Defualt: " & device.WaveOutCaps.szPname
End Sub
Private Function GetIdOfDefaultWaveOutDevice() As Integer
Dim id As Integer = 0
Dim hId As IntPtr
Dim flags As Integer = 0
Dim hFlags As IntPtr
Dim result As Integer
Try
' It would be easier to declare a nice overload with ByRef Integers.
hId = Marshal.AllocHGlobal(4)
hFlags = Marshal.AllocHGlobal(4)
' http://msdn.microsoft.com/en-us/library/bb981557.aspx
result = waveOut.Message(WAVE_MAPPER, DRVM_MAPPER_PREFERRED_GET, hId, hFlags)
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("waveOutMessage() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
id = Marshal.ReadInt32(hId)
flags = Marshal.ReadInt32(hFlags)
Finally
Marshal.FreeHGlobal(hId)
Marshal.FreeHGlobal(hFlags)
End Try
' There is only one flag, DRVM_MAPPER_PREFERRED_FLAGS_PREFERREDONLY, defined as 1
' "When the DRVM_MAPPER_PREFERRED_FLAGS_PREFERREDONLY flag bit is set, ... blah ...,
' the waveIn and waveOut APIs use only the current preferred device and do not search
' for other available devices if the preferred device is unavailable.
Return id
End Function
Private Sub SetDefaultButton_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles SetDefaultButton.Click
If DevicesComboBox.Items.Count = 0 Then Return
Dim selectedDevice As WaveOutDevice = DirectCast(DevicesComboBox.SelectedItem, WaveOutDevice)
SetDefault(selectedDevice.Id)
RefreshInformation()
End Sub
Private Sub SetDefault(ByVal id As Integer)
Dim defaultId As Integer = GetIdOfDefaultWaveOutDevice()
If defaultId = id Then Return ' no change.
Dim result As Integer
' So here we say "change the Id of the device that has id id to 0", which makes it the default.
result = waveOut.Message(WAVE_MAPPER, DRVM_MAPPER_PREFERRED_SET, New IntPtr(id), IntPtr.Zero)
If result <> MMSYSERR.NoError Then
Dim err As MMSYSERR = DirectCast(result, MMSYSERR)
Throw New Win32Exception("waveOutMessage() error, Result: " & result.ToString("x8") & ", " & err.ToString)
End If
End Sub
End Class
System.Management
You can retrieve the available audio devices using System.Management assembly which is a part of .Net framework:
ManagementObjectSearcher mo =
new ManagementObjectSearcher("select * from Win32_SoundDevice");
foreach (ManagementObject soundDevice in mo.Get())
{
String deviceId = soundDevice.GetPropertyValue("DeviceId").ToString();
String name = soundDevice.GetPropertyValue("Name").ToString();
//saving the name and device id in array
}
References
Get list of audio devices and select one using c# (Another solution provided in this link (using Lync 2013 SDK)
Win32_SoundDevice class
I am new to stackoverflow but I registered because I think here is the right place to get professional help for programming :)
My goal is to create a webcam snapshot tool which directly saves the snapshot to a file.
I don't need any preview in a picturebox or something like that.
I am thinking about a application like this:
A simple Interface with a Combobox for the connected webcam devices and one button which will take a snapshot and saves it to a file.
I like to use DirectShow for this because all other ways using AForge or advcap32.dll, because they sometimes cause
a Videosourcedialog to popup, which I don't want to.
I like to select a webcamdevice in my combobox manually and be able to take a snapshot.
So that way I like to use DirectShow.
I already added the DirectShowLib-2005.dll to my VB.Net Project
And I also added this class:
Imports System
Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.Runtime.InteropServices
Imports System.Diagnostics
Imports DirectShowLib
Public Class Capture
Implements ISampleGrabberCB
Implements IDisposable
#Region "Member variables"
Private m_graphBuilder As IFilterGraph2 = Nothing
Private m_mediaCtrl As IMediaControl = Nothing
Private mediaEventEx As IMediaEventEx = Nothing
Private videoWindow As IVideoWindow = Nothing
Private UseHand As IntPtr = MainForm.PictureBox1.Handle
Private Const WMGraphNotify As Integer = 13
Private m_takePicture As Boolean = False
Public mytest As String = "yes"
Dim sampGrabber As ISampleGrabber = Nothing
Private bufferedSize As Integer = 0
Private savedArray() As Byte
Public capturedPic As bitmap
Public captureSaved As Boolean
Public unsupportedVideo As Boolean
' <summary> Set by async routine when it captures an image </summary>
Public m_bRunning As Boolean = False
' <summary> Dimensions of the image, calculated once in constructor. </summary>
Private m_videoWidth As Integer
Private m_videoHeight As Integer
Private m_stride As Integer
Private m_bmdLogo As BitmapData = Nothing
Private m_Bitmap As Bitmap = Nothing
#If DEBUG Then
' Allow you to "Connect to remote graph" from GraphEdit
Private m_rot As DsROTEntry = Nothing
#End If
#End Region
#Region "API"
Declare Sub CopyMemory Lib "Kernel32.dll" Alias "RtlMoveMemory" (ByVal Destination As IntPtr, ByVal Source As IntPtr, <MarshalAs(UnmanagedType.U4)> ByVal Length As Integer)
#End Region
' zero based device index, and some device parms, plus the file name to save to
Public Sub New(ByVal iDeviceNum As Integer, ByVal iFrameRate As Integer, ByVal iWidth As Integer, ByVal iHeight As Integer)
Dim capDevices As DsDevice()
' Get the collection of video devices
capDevices = DsDevice.GetDevicesOfCat(FilterCategory.VideoInputDevice)
If (iDeviceNum + 1 > capDevices.Length) Then
Throw New Exception("No video capture devices found at that index!")
End If
Dim dev As DsDevice = capDevices(iDeviceNum)
Try
' Set up the capture graph
SetupGraph(dev, iFrameRate, iWidth, iHeight)
Catch
Dispose()
If unsupportedVideo Then
msgbox("This video resolution isn't supported by the camera - please choose a different resolution.")
Else
Throw
End If
End Try
End Sub
' <summary> release everything. </summary>
Public Sub Dispose() Implements IDisposable.Dispose
CloseInterfaces()
If (Not m_Bitmap Is Nothing) Then
m_Bitmap.UnlockBits(m_bmdLogo)
m_Bitmap = Nothing
m_bmdLogo = Nothing
End If
End Sub
Protected Overloads Overrides Sub finalize()
CloseInterfaces()
End Sub
' <summary> capture the next image </summary>
Public Sub Start()
If (m_bRunning = False) Then
Dim hr As Integer = m_mediaCtrl.Run()
DsError.ThrowExceptionForHR(hr)
m_bRunning = True
End If
End Sub
' Pause the capture graph.
' Running the graph takes up a lot of resources. Pause it when it
' isn't needed.
Public Sub Pause()
If (m_bRunning) Then
Dim hr As Integer = m_mediaCtrl.Pause()
DsError.ThrowExceptionForHR(hr)
m_bRunning = False
End If
End Sub
'Added by jk
Public Sub TakePicture()
m_takePicture = True
End Sub
' <summary> Specify the logo file to write onto each frame </summary>
Public Sub SetLogo(ByVal fileName As String)
SyncLock Me
If (fileName.Length > 0) Then
m_Bitmap = New Bitmap(fileName)
Dim r As Rectangle = New Rectangle(0, 0, m_Bitmap.Width, m_Bitmap.Height)
m_bmdLogo = m_Bitmap.LockBits(r, ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb)
Else
If Not m_Bitmap Is Nothing Then
m_Bitmap.UnlockBits(m_bmdLogo)
m_Bitmap = Nothing
m_bmdLogo = Nothing
End If
End If
End SyncLock
End Sub
' <summary> build the capture graph for grabber. </summary>
Private Sub SetupGraph(ByVal dev As DsDevice, ByVal iFrameRate As Integer, ByVal iWidth As Integer, ByVal iHeight As Integer)
Dim hr As Integer
Dim baseGrabFlt As IBaseFilter = Nothing
Dim capFilter As IBaseFilter = Nothing
Dim muxFilter As IBaseFilter = Nothing
Dim fileWriterFilter As IFileSinkFilter = Nothing
Dim capGraph As ICaptureGraphBuilder2 = Nothing
Dim sampGrabberSnap As ISampleGrabber = Nothing
' Get the graphbuilder object
m_graphBuilder = DirectCast(New FilterGraph(), IFilterGraph2)
m_mediaCtrl = DirectCast(m_graphBuilder, IMediaControl)
'if taking a picture (a still snapshot), then remove the videowindow
If Not m_takePicture Then
mediaEventEx = DirectCast(m_graphBuilder, IMediaEventEx)
videoWindow = DirectCast(m_graphBuilder, IVideoWindow)
Else
mediaEventEx = Nothing
videoWindow = Nothing
End If
#If DEBUG Then
m_rot = New DsROTEntry(m_graphBuilder)
#End If
Try
' Get the ICaptureGraphBuilder2
capGraph = DirectCast(New CaptureGraphBuilder2(), ICaptureGraphBuilder2)
' Get the SampleGrabber interface
sampGrabber = DirectCast(New SampleGrabber(), ISampleGrabber)
sampGrabberSnap = DirectCast(New SampleGrabber(), ISampleGrabber)
' Start building the graph
hr = capGraph.SetFiltergraph(DirectCast(m_graphBuilder, IGraphBuilder))
DsError.ThrowExceptionForHR(hr)
' Add the video device
hr = m_graphBuilder.AddSourceFilterForMoniker(dev.Mon, Nothing, dev.Name, capFilter)
DsError.ThrowExceptionForHR(hr)
baseGrabFlt = DirectCast(sampGrabber, IBaseFilter)
ConfigureSampleGrabber(sampGrabber)
' Add the frame grabber to the graph
hr = m_graphBuilder.AddFilter(baseGrabFlt, "Ds.NET Grabber")
DsError.ThrowExceptionForHR(hr)
' If any of the default config items are set
If (iFrameRate + iHeight + iWidth > 0) Then
SetConfigParms(capGraph, capFilter, iFrameRate, iWidth, iHeight)
End If
hr = capGraph.RenderStream(PinCategory.Capture, MediaType.Video, capFilter, baseGrabFlt, muxFilter)
DsError.ThrowExceptionForHR(hr)
'if you set the m_takePicture it won't
If Not m_takePicture Then
'Set the output of the preview
hr = mediaEventEx.SetNotifyWindow(UseHand, WMGraphNotify, IntPtr.Zero)
DsError.ThrowExceptionForHR(hr)
'Set Owner to Display Video
hr = videoWindow.put_Owner(UseHand)
DsError.ThrowExceptionForHR(hr)
'Set window location - this was necessary so that the video didn't move down and to the right when you pushed the start/stop button
hr = videoWindow.SetWindowPosition(0, 0, 320, 240)
DsError.ThrowExceptionForHR(hr)
'Set Owner Video Style
hr = videoWindow.put_WindowStyle(WindowStyle.Child)
DsError.ThrowExceptionForHR(hr)
End If
SaveSizeInfo(sampGrabber)
Finally
If (Not fileWriterFilter Is Nothing) Then
Marshal.ReleaseComObject(fileWriterFilter)
fileWriterFilter = Nothing
End If
If (Not muxFilter Is Nothing) Then
Marshal.ReleaseComObject(muxFilter)
muxFilter = Nothing
End If
If (Not capFilter Is Nothing) Then
Marshal.ReleaseComObject(capFilter)
capFilter = Nothing
End If
If (Not sampGrabber Is Nothing) Then
Marshal.ReleaseComObject(sampGrabber)
sampGrabber = Nothing
End If
End Try
End Sub
' <summary> Read and store the properties </summary>
Private Sub SaveSizeInfo(ByVal sampGrabber As ISampleGrabber)
Dim hr As Integer
' Get the media type from the SampleGrabber
Dim media As AMMediaType = New AMMediaType()
hr = sampGrabber.GetConnectedMediaType(media)
DsError.ThrowExceptionForHR(hr)
If (Not (media.formatType.Equals(FormatType.VideoInfo)) AndAlso Not (media.formatPtr.Equals(IntPtr.Zero))) Then
Throw New NotSupportedException("Unknown Grabber Media Format")
End If
' Grab the size info
Dim vInfoHeader As VideoInfoHeader = New VideoInfoHeader()
Marshal.PtrToStructure(media.formatPtr, vInfoHeader)
m_videoWidth = vInfoHeader.BmiHeader.Width
m_videoHeight = vInfoHeader.BmiHeader.Height
m_stride = CInt(m_videoWidth * (vInfoHeader.BmiHeader.BitCount / 8))
DsUtils.FreeAMMediaType(media)
media = Nothing
End Sub
' <summary> Set the options on the sample grabber </summary>
Private Sub ConfigureSampleGrabber(ByVal sampGrabber As ISampleGrabber)
Dim hr As Integer
Dim media As AMMediaType = New AMMediaType()
media.majorType = MediaType.Video
media.subType = MediaSubType.RGB24
media.formatType = FormatType.VideoInfo
hr = sampGrabber.SetMediaType(media)
DsError.ThrowExceptionForHR(hr)
DsUtils.FreeAMMediaType(media)
media = Nothing
' Configure the samplegrabber callback
hr = sampGrabber.SetOneShot(False)
DsError.ThrowExceptionForHR(hr)
If m_takePicture Then
hr = sampGrabber.SetCallback(Me, 0)
Else
hr = sampGrabber.SetCallback(Me, 0)
End If
DsError.ThrowExceptionForHR(hr)
DsError.ThrowExceptionForHR(hr)
'set the samplegrabber
sampGrabber.SetBufferSamples(False)
End Sub
' Set the Framerate, and video size
Private Sub SetConfigParms(ByVal capGraph As ICaptureGraphBuilder2, ByVal capFilter As IBaseFilter, ByVal iFrameRate As Integer, ByVal iWidth As Integer, ByVal iHeight As Integer)
Dim hr As Integer
Dim o As Object = Nothing
Dim media As AMMediaType = Nothing
Dim videoStreamConfig As IAMStreamConfig
Dim videoControl As IAMVideoControl = DirectCast(capFilter, IAMVideoControl)
' Find the stream config interface
hr = capGraph.FindInterface(PinCategory.Capture, MediaType.Video, capFilter, GetType(IAMStreamConfig).GUID, o)
videoStreamConfig = DirectCast(o, IAMStreamConfig)
Try
If (videoStreamConfig Is Nothing) Then
Throw New Exception("Failed to get IAMStreamConfig")
End If
' Get the existing format block
hr = videoStreamConfig.GetFormat(media)
DsError.ThrowExceptionForHR(hr)
' copy out the videoinfoheader
Dim v As VideoInfoHeader = New VideoInfoHeader()
Marshal.PtrToStructure(media.formatPtr, v)
' if overriding the framerate, set the frame rate
If (iFrameRate > 0) Then
v.AvgTimePerFrame = CLng(10000000 / iFrameRate)
End If
' if overriding the width, set the width
If (iWidth > 0) Then
v.BmiHeader.Width = iWidth
End If
' if overriding the Height, set the Height
If (iHeight > 0) Then
v.BmiHeader.Height = iHeight
End If
' Copy the media structure back
Marshal.StructureToPtr(v, media.formatPtr, False)
' Set the new format
hr = videoStreamConfig.SetFormat(media)
If hr <> 0 Then unsupportedVideo = True Else unsupportedVideo = False
DsError.ThrowExceptionForHR(hr)
DsUtils.FreeAMMediaType(media)
media = Nothing
' Fix upsidedown video
If (Not videoControl Is Nothing) Then
Dim pCapsFlags As VideoControlFlags
Dim pPin As IPin = DsFindPin.ByCategory(capFilter, PinCategory.Capture, 0)
hr = videoControl.GetCaps(pPin, pCapsFlags)
DsError.ThrowExceptionForHR(hr)
If (CDbl(pCapsFlags & VideoControlFlags.FlipVertical) > 0) Then
hr = videoControl.GetMode(pPin, pCapsFlags)
DsError.ThrowExceptionForHR(hr)
hr = videoControl.SetMode(pPin, 0)
End If
End If
Finally
Marshal.ReleaseComObject(videoStreamConfig)
End Try
End Sub
' <summary> Shut down capture </summary>
Private Sub CloseInterfaces()
Dim hr As Integer
Try
If (Not m_mediaCtrl Is Nothing) Then
' Stop the graph
hr = m_mediaCtrl.Stop()
m_mediaCtrl = Nothing
m_bRunning = False
'Release Window Handle, Reset back to Normal
hr = videoWindow.put_Visible(OABool.False)
DsError.ThrowExceptionForHR(hr)
hr = videoWindow.put_Owner(IntPtr.Zero)
DsError.ThrowExceptionForHR(hr)
If mediaEventEx Is Nothing = False Then
hr = mediaEventEx.SetNotifyWindow(IntPtr.Zero, 0, IntPtr.Zero)
DsError.ThrowExceptionForHR(hr)
End If
End If
Catch ex As Exception
Debug.WriteLine(ex)
End Try
#If DEBUG Then
If (Not m_rot Is Nothing) Then
m_rot.Dispose()
m_rot = Nothing
End If
#End If
If (Not m_graphBuilder Is Nothing) Then
Marshal.ReleaseComObject(m_graphBuilder)
m_graphBuilder = Nothing
End If
GC.Collect()
End Sub
' <summary> sample callback, Originally not used - call this with integer 0 on the setcallback method </summary>
Function SampleCB(ByVal SampleTime As Double, ByVal pSample As IMediaSample) As Integer Implements ISampleGrabberCB.SampleCB
myTest = "In SampleCB"
Dim i As Integer = 0
'jk added this code 10-22-13
If IsDBNull(pSample) = True Then Return -1
Dim myLen As Integer = pSample.GetActualDataLength()
Dim pbuf As IntPtr
If pSample.GetPointer(pbuf) = 0 And mylen > 0 Then
Dim buf As Byte() = New Byte(myLen) {}
Marshal.Copy(pbuf, buf, 0, myLen)
'Alter the video - you could use this to adjust the brightness/red/green, etc.
'for i = myLen-1 to 0 step -1
' buf(i) = (255 - buf(i))
'Next i
If m_takePicture Then
Dim bm As New Bitmap(m_videoWidth, m_videoHeight, Imaging.PixelFormat.Format24bppRgb)
Dim g_RowSizeBytes As Integer
Dim g_PixBytes() As Byte
mytest = "Execution point #1"
Dim m_BitmapData As BitmapData = Nothing
Dim bounds As Rectangle = New Rectangle(0, 0, m_videoWidth, m_videoHeight)
mytest = "Execution point #2"
m_BitmapData = bm.LockBits(bounds, Imaging.ImageLockMode.ReadWrite, Imaging.PixelFormat.Format24bppRgb)
mytest = "Execution point #4"
g_RowSizeBytes = m_BitmapData.Stride
mytest = "Execution point #5"
' Allocate room for the data.
Dim total_size As Integer = m_BitmapData.Stride * m_BitmapData.Height
ReDim g_PixBytes(total_size)
mytest = "Execution point #10"
'this writes the data to the Bitmap
Marshal.Copy(buf, 0, m_BitmapData.Scan0, mylen)
capturedPic = bm
mytest = "Execution point #15"
' Release resources.
bm.UnlockBits(m_BitmapData)
g_PixBytes = Nothing
m_BitmapData = Nothing
bm = Nothing
buf = Nothing
m_takePicture = False
captureSaved = True
mytest = "Execution point #20"
End If
End If
Marshal.ReleaseComObject(pSample)
Return 0
End Function
' <summary> buffer callback, Not used - call this with integer 1 on the setcallback method </summary>
Function BufferCB(ByVal SampleTime As Double, ByVal pBuffer As IntPtr, ByVal BufferLen As Integer) As Integer Implements ISampleGrabberCB.BufferCB
SyncLock Me
myTest = "In BufferCB"
End SyncLock
Return 0
End Function
End Class
Can someone help to achieve my goal described above.
1) Enumerating Devices in Combobox
2) Snapshot selected webcam device to a file.
Any help is appreciated :)
I'm using AForge (My program does a bit more, but this will give you a start)
Mine does not pop-up the dialog, because it enumerates it itself (You may want just that code chunk)
You can also set all the My.Settings to hard-coded settings.
This does create a display for the video, but you can simply set vspMonitor.visible = False if you don't want it to display.
Imports AForge.Controls
Imports AForge.Video
Imports AForge.Video.DirectShow
Imports AForge.Video.VFW
Imports System.IO
Public Class Main
Private WithEvents timer As New Timer
'Stores the file path, e.g.: "F:\Temp"
Friend Shared strICLocation As String = My.Settings.ICSet
'Stores the common name for the file, such as "Capture" (Screenshot, whatever you want)
Friend Shared strICFileRootName As String = My.Settings.ICRootName
'Stores the image format to save in a 3 char string: PNG, JPG, BMP
Friend Shared strICType As String = My.Settings.ICType
Dim VideoCaptureSource As VideoCaptureDevice
Dim VideoDevices As New FilterInfoCollection(FilterCategory.VideoInputDevice)
Private Property VideoCapabilities As VideoCapabilities()
Dim frame As System.Drawing.Bitmap
Dim filename As String
Private Sub Main_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'You'll need the following items in your UI at minimum:
'Button named btnConnect, button named btnDisconnect, Video Source Player (From AForge libraries) named vspMonitor, a Combo Box named cmbVideoSource
EnumerateVideoDevices()
btnDisconnect.Enabled = False
btnConnect.Enabled = True
strICFileRootName = My.Settings.ICRootName
strICLocation = My.Settings.ICSet
lblICLocation.Text = strICLocation
End Sub
Private Sub EnumerateVideoDevices()
' enumerate video devices
VideoDevices = New FilterInfoCollection(FilterCategory.VideoInputDevice)
If VideoDevices.Count <> 0 Then
' add all devices to combo
For Each device As FilterInfo In VideoDevices
cmbVideoSource.Items.Add(device.Name)
cmbVideoSource.SelectedIndex = 0
VideoCaptureSource = New VideoCaptureDevice(VideoDevices(cmbVideoSource.SelectedIndex).MonikerString)
EnumerateVideoModes(VideoCaptureSource)
Next
Else
cmbVideoSource.Items.Add("No DirectShow devices found")
End If
cmbVideoSource.SelectedIndex = 0
End Sub
Private Sub EnumerateVideoModes(device As VideoCaptureDevice)
' get resolutions for selected video source
Me.Cursor = Cursors.WaitCursor
cmbVideoModes.Items.Clear()
Try
Dim VideoCapabilities = device.VideoCapabilities
For Each capabilty As VideoCapabilities In VideoCapabilities
If Not cmbVideoModes.Items.Contains(capabilty.FrameSize) Then
cmbVideoModes.Items.Add(capabilty.FrameSize)
End If
Next
If VideoCapabilities.Length = 0 Then
cmbVideoModes.Items.Add("Not supported")
End If
cmbVideoModes.SelectedIndex = 0
Finally
Me.Cursor = Cursors.[Default]
End Try
End Sub
#Region "IC (Image Capture)"
Private Sub btnICOptions_Click(sender As Object, e As EventArgs) Handles btnICOptions.Click
' I use a form to set to image save type; handle it however you want, including hard-coding it
Dim frm As New frmICOptions
frm.Show()
End Sub
Private Sub btnICSet_Click(sender As Object, e As EventArgs) Handles btnICSet.Click
'Make a button called btnICSet to set the save path
Dim dialog As New FolderBrowserDialog()
dialog.Description = "Select Image Capture save path"
If dialog.ShowDialog() = Windows.Forms.DialogResult.OK Then
strICLocation = dialog.SelectedPath
lblICLocation.Text = strICLocation
End If
End Sub
Private Sub ICCapture_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnICCapture.Click
'Need a button called btnICCapture. This is what will initiate the screen cap.
Try
If vspMonitor.IsRunning = True Then
If My.Settings.ICType = "PNG" Then
Dim strFilename As String = strICFileRootName & " " & Format(Now, "yyyy-MMM-dd HH.mm.ss.fff") & ".png"
vspMonitor.GetCurrentVideoFrame.Save(strICLocation & "\" & strFilename, System.Drawing.Imaging.ImageFormat.Png)
ElseIf My.Settings.ICType = "JPG" Then
Dim strFilename As String = strICFileRootName & " " & Format(Now, "yyyy-MMM-dd HH.mm.ss.fff") & ".jpg"
vspMonitor.GetCurrentVideoFrame.Save(strICLocation & "\" & strFilename, System.Drawing.Imaging.ImageFormat.Jpeg)
Else
Dim strFilename As String = strICFileRootName & " " & Format(Now, "yyyy-MMM-dd HH.mm.ss.fff") & ".bmp"
vspMonitor.GetCurrentVideoFrame.Save(strICLocation & "\" & strFilename, System.Drawing.Imaging.ImageFormat.Bmp)
End If
End If
Catch ex As Exception
MessageBox.Show("Try taking snapshot again when video image is visible.", "Cannot Save Image", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try
End Sub
#End Region
End Class
There may be some extraneous (to your purpose) variables and settings (my app does Image capture, screen capture, video capture, Stop Motion capture (to images or video) and Motion Detect Capture to video, so I basically yanked this code from it trying to get you in the right direction.) I'll be happy to modify it if I've left any errors.
how i can show textbox in FolderBrowserDialog like below image,
This is not directly possible, you have to fallback to using the shell function. Project + Add Reference, Browse tab, select c:\windows\system32\shell32.dll. An example of how to use it in a Winforms app:
Private Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click
Dim options As Integer = &H40 + &H200 + &H20
options += &H10 '' Adds edit box
Dim shell = New Shell32.ShellClass
Dim root = Environment.GetFolderPath(Environment.SpecialFolder.Desktop)
Dim folder = CType(shell.BrowseForFolder(CInt(Me.Handle), _
"Select folder", options, root), Shell32.Folder2)
If folder IsNot Nothing Then
MsgBox("You selected " + folder.Self.Path)
End If
End Sub
Check this out : FolderBrowserDialogEx: A C# customization of FolderBrowserDialog
The code is in C#, Here is the VB Conversion
Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Text
Imports System.Drawing
Imports System.Runtime.InteropServices
Imports System.Windows.Forms
Imports System.Diagnostics
Namespace DaveChambers.FolderBrowserDialogEx
Public Class FolderBrowserDialogEx
#Region "Fields that mimic the same-named fields in FolderBrowserDialog"
Public Property RootFolder() As Environment.SpecialFolder
Get
Return m_RootFolder
End Get
Set
m_RootFolder = Value
End Set
End Property
Private m_RootFolder As Environment.SpecialFolder
Public Property SelectedPath() As String
Get
Return m_SelectedPath
End Get
Set
m_SelectedPath = Value
End Set
End Property
Private m_SelectedPath As String
Public Property ShowNewFolderButton() As Boolean
Get
Return m_ShowNewFolderButton
End Get
Set
m_ShowNewFolderButton = Value
End Set
End Property
Private m_ShowNewFolderButton As Boolean
Public Property StartPosition() As FormStartPosition
Get
Return m_StartPosition
End Get
Set
m_StartPosition = Value
End Set
End Property
Private m_StartPosition As FormStartPosition
#End Region
' Fields specific to CustomFolderBrowserDialog
Public Property Title() As String
Get
Return m_Title
End Get
Set
m_Title = Value
End Set
End Property
Private m_Title As String
Public Property ShowEditbox() As Boolean
Get
Return m_ShowEditbox
End Get
Set
m_ShowEditbox = Value
End Set
End Property
Private m_ShowEditbox As Boolean
' These are the control IDs used in the dialog
Private Structure CtlIds
Public Const PATH_EDIT As Integer = &H3744
'public const int PATH_EDIT_LABEL = 0x3748; // Only when BIF_NEWDIALOGSTYLE
Public Const TITLE As Integer = &H3742
Public Const TREEVIEW As Integer = &H3741
Public Const NEW_FOLDER_BUTTON As Integer = &H3746
Public Const IDOK As Integer = 1
Public Const IDCANCEL As Integer = 2
End Structure
<StructLayout(LayoutKind.Sequential, CharSet := CharSet.Unicode)> _
Public Structure InitData
' Titles shouldn't too long, should they?
<MarshalAs(UnmanagedType.ByValTStr, SizeConst := 128)> _
Public Title As String
<MarshalAs(UnmanagedType.ByValTStr, SizeConst := Win32.MAX_PATH)> _
Public InitialPath As String
Public ShowEditbox As Boolean
Public ShowNewFolderButton As Boolean
Public StartPosition As FormStartPosition
Public hParent As IntPtr
Public Sub New(dlg As FolderBrowserDialogEx, hParent As IntPtr)
' We need to make copies of these values from the dialog.
' I tried passing the dlg obj itself in this struct, but Windows will barf after repeated invocations.
Me.Title = dlg.Title
Me.InitialPath = dlg.SelectedPath
Me.ShowNewFolderButton = dlg.ShowNewFolderButton
Me.ShowEditbox = dlg.ShowEditbox
Me.StartPosition = dlg.StartPosition
Me.hParent = hParent
End Sub
End Structure
Public Sub New()
Title = "Browse For Folder"
' Default to same caption as std dialog
RootFolder = Environment.SpecialFolder.Desktop
SelectedPath = "c:\"
ShowEditbox = False
ShowNewFolderButton = False
StartPosition = FormStartPosition.WindowsDefaultLocation
End Sub
Public Function ShowDialog(owner As IWin32Window) As DialogResult
Dim initdata As New InitData(Me, owner.Handle)
Dim bi As New Win32.BROWSEINFO()
bi.iImage = 0
bi.hwndOwner = owner.Handle
If 0 <> Win32.SHGetSpecialFolderLocation(owner.Handle, CInt(Me.RootFolder), bi.pidlRoot) Then
bi.pidlRoot = IntPtr.Zero
End If
bi.lpszTitle = ""
bi.ulFlags = Win32.BIF_RETURNONLYFSDIRS
' do NOT use BIF_NEWDIALOGSTYLE or BIF_STATUSTEXT
If Me.ShowEditbox Then
bi.ulFlags = bi.ulFlags Or Win32.BIF_EDITBOX
End If
If Not Me.ShowNewFolderButton Then
bi.ulFlags = bi.ulFlags Or Win32.BIF_NONEWFOLDERBUTTON
End If
bi.lpfn = New Win32.BrowseCallbackProc(_browseCallbackHandler)
' Initialization data, used in _browseCallbackHandler
Dim hInit As IntPtr = Marshal.AllocHGlobal(Marshal.SizeOf(initdata))
Marshal.StructureToPtr(initdata, hInit, True)
bi.lParam = hInit
Dim pidlSelectedPath As IntPtr = IntPtr.Zero
Try
pidlSelectedPath = Win32.SHBrowseForFolder(bi)
Dim sb As New StringBuilder(256)
If Win32.SHGetPathFromIDList(pidlSelectedPath, sb) Then
SelectedPath = sb.ToString()
Return DialogResult.OK
End If
Finally
' Caller is responsible for freeing this memory.
Marshal.FreeCoTaskMem(pidlSelectedPath)
End Try
Return DialogResult.Cancel
End Function
Private Function _browseCallbackHandler(hDlg As IntPtr, msg As Integer, lParam As IntPtr, lpData As IntPtr) As Integer
Select Case msg
Case Win32.BFFM_INITIALIZED
' remove context help button from dialog caption
Dim lStyle As Integer = Win32.GetWindowLong(hDlg, Win32.GWL_STYLE)
lStyle = lStyle And Not Win32.DS_CONTEXTHELP
Win32.SetWindowLong(hDlg, Win32.GWL_STYLE, lStyle)
lStyle = Win32.GetWindowLong(hDlg, Win32.GWL_EXSTYLE)
lStyle = lStyle And Not Win32.WS_EX_CONTEXTHELP
Win32.SetWindowLong(hDlg, Win32.GWL_EXSTYLE, lStyle)
_adjustUi(hDlg, lpData)
Exit Select
Case Win32.BFFM_SELCHANGED
If True Then
Dim ok As Boolean = False
Dim sb As New StringBuilder(Win32.MAX_PATH)
If Win32.SHGetPathFromIDList(lParam, sb) Then
ok = True
Dim dir As String = sb.ToString()
Dim hEdit As IntPtr = Win32.GetDlgItem(hDlg, CtlIds.PATH_EDIT)
Win32.SetWindowText(hEdit, dir)
#If UsingStatusText Then
' We're not using status text, but if we were, this is how you'd set it
Win32.SendMessage(hDlg, Win32.BFFM_SETSTATUSTEXTW, 0, dir)
#End If
#If SHBrowseForFolder_lists_links Then
' This check doesn't seem to be necessary - the SHBrowseForFolder dirtree doesn't seem to list links
Dim sfi As New Win32.SHFILEINFO()
Win32.SHGetFileInfo(lParam, 0, sfi, Marshal.SizeOf(sfi), Win32.SHGFI_PIDL Or Win32.SHGFI_ATTRIBUTES)
' fail if pidl is a link
If (sfi.dwAttributes And Win32.SFGAO_LINK) = Win32.SFGAO_LINK Then
ok = False
#End If
End If
End If
' if invalid selection, disable the OK button
If Not ok Then
Win32.EnableWindow(Win32.GetDlgItem(hDlg, CtlIds.IDOK), False)
End If
Exit Select
End If
End Select
Return 0
End Function
Private Sub _adjustUi(hDlg As IntPtr, lpData As IntPtr)
' Only do the adjustments if InitData was supplied
If lpData = IntPtr.Zero Then
Return
End If
Dim obj As Object = Marshal.PtrToStructure(lpData, GetType(InitData))
If obj Is Nothing Then
Return
End If
Dim initdata As InitData = DirectCast(obj, InitData)
' Only do the adjustments if we can find the dirtree control
Dim hTree As IntPtr = Win32.GetDlgItem(hDlg, CtlIds.TREEVIEW)
If hTree = IntPtr.Zero Then
hTree = Win32.FindWindowEx(IntPtr.Zero, IntPtr.Zero, "SysTreeView32", IntPtr.Zero)
If hTree = IntPtr.Zero Then
' This usually means that BIF_NEWDIALOGSTYLE is enabled.
hTree = Win32.FindWindowEx(hDlg, IntPtr.Zero, "SHBrowseForFolder ShellNameSpace Control", IntPtr.Zero)
End If
End If
If hTree = IntPtr.Zero Then
Return
End If
' Prep the basic UI
Win32.SendMessage(hDlg, Win32.BFFM_SETSELECTIONW, 1, initdata.InitialPath)
Win32.SetWindowText(hDlg, initdata.Title)
If initdata.StartPosition = FormStartPosition.CenterParent Then
_centerTo(hDlg, initdata.hParent)
ElseIf initdata.StartPosition = FormStartPosition.CenterScreen Then
_centerTo(hDlg, Win32.GetDesktopWindow())
End If
' else we do nothing
' Prep the edit box
Dim rcEdit As New Win32.RECT()
Dim hEdit As IntPtr = Win32.GetDlgItem(hDlg, CtlIds.PATH_EDIT)
If hEdit <> IntPtr.Zero Then
If initdata.ShowEditbox Then
Win32.GetWindowRect(hEdit, rcEdit)
Win32.ScreenToClient(hEdit, rcEdit)
Else
Win32.ShowWindow(hEdit, Win32.SW_HIDE)
End If
End If
' make the dialog larger
Dim rcDlg As Win32.RECT
Win32.GetWindowRect(hDlg, rcDlg)
rcDlg.Right += 40
rcDlg.Bottom += 30
If hEdit <> IntPtr.Zero Then
rcDlg.Bottom += (rcEdit.Height + 5)
End If
Win32.MoveWindow(hDlg, rcDlg, True)
Win32.GetClientRect(hDlg, rcDlg)
Dim vMargin As Integer = 10
' Accomodate the resizing handle's width
Dim hMargin As Integer = 10
' SystemInformation.VerticalScrollBarWidth;
' Move the Cancel button
Dim rcCancel As New Win32.RECT()
Dim hCancel As IntPtr = Win32.GetDlgItem(hDlg, CtlIds.IDCANCEL)
If hCancel <> IntPtr.Zero Then
Win32.GetWindowRect(hCancel, rcCancel)
Win32.ScreenToClient(hDlg, rcCancel)
rcCancel = New Win32.RECT(rcDlg.Right - (rcCancel.Width + hMargin), rcDlg.Bottom - (rcCancel.Height + vMargin), rcCancel.Width, rcCancel.Height)
Win32.MoveWindow(hCancel, rcCancel, False)
End If
' Move the OK button
Dim rcOK As New Win32.RECT()
Dim hOK As IntPtr = Win32.GetDlgItem(hDlg, CtlIds.IDOK)
If hOK <> IntPtr.Zero Then
Win32.GetWindowRect(hOK, rcOK)
Win32.ScreenToClient(hDlg, rcOK)
rcOK = New Win32.RECT(rcCancel.Left - (rcCancel.Width + hMargin), rcCancel.Top, rcOK.Width, rcOK.Height)
Win32.MoveWindow(hOK, rcOK, False)
End If
' Manage the "Make New Folder" button
Dim hBtn As IntPtr = Win32.GetDlgItem(hDlg, CtlIds.NEW_FOLDER_BUTTON)
If Not initdata.ShowNewFolderButton Then
' Make sure this button is not visible
Win32.ShowWindow(hBtn, Win32.SW_HIDE)
ElseIf hBtn = IntPtr.Zero Then
' Create a button - button is only auto-created under BIF_NEWDIALOGSTYLE
' This is failing, and I don't know why!
hBtn = Win32.CreateWindowEx(&H50010000, "button", "&Make New Folder", &H4, hMargin, rcOK.Top, _
105, rcOK.Height, hDlg, New IntPtr(CtlIds.NEW_FOLDER_BUTTON), Process.GetCurrentProcess().Handle, IntPtr.Zero)
End If
' Position the path editbox and it's label
' We'll repurpose the Title (static) control as the editbox label
Dim treeTop As Integer = vMargin
If hEdit <> IntPtr.Zero Then
Dim xEdit As Integer = hMargin
Dim cxEdit As Integer = rcDlg.Width - (2 * hMargin)
Dim hLabel As IntPtr = Win32.GetDlgItem(hDlg, CtlIds.TITLE)
If hLabel <> IntPtr.Zero Then
Dim labelText As String = "Folder: "
Win32.SetWindowText(hLabel, labelText)
' This code obtains the required size of the static control that serves as the label for the editbox.
' All this GDI code is a bit excessive, but I figured "what the hell".
Dim hdc As IntPtr = Win32.GetDC(hLabel)
Dim hFont As IntPtr = Win32.SendMessage(hLabel, Win32.WM_GETFONT, IntPtr.Zero, IntPtr.Zero)
Dim oldfnt As IntPtr = Win32.SelectObject(hdc, hFont)
Dim szLabel As Size = Size.Empty
Win32.GetTextExtentPoint32(hdc, labelText, labelText.Length, szLabel)
Win32.SelectObject(hdc, oldfnt)
Win32.ReleaseDC(hLabel, hdc)
Dim rcLabel As New Win32.RECT(hMargin, vMargin + ((rcEdit.Height - szLabel.Height) / 2), szLabel.Width, szLabel.Height)
Win32.MoveWindow(hLabel, rcLabel, False)
xEdit += rcLabel.Width
cxEdit -= rcLabel.Width
End If
' Expand the folder tree to fill the dialog
rcEdit = New Win32.RECT(xEdit, vMargin, cxEdit, rcEdit.Height)
Win32.MoveWindow(hEdit, rcEdit, False)
treeTop = rcEdit.Bottom + 5
End If
Dim rcTree As New Win32.RECT(hMargin, treeTop, rcDlg.Width - (2 * hMargin), rcDlg.Bottom - (treeTop + (2 * vMargin) + rcOK.Height))
Win32.MoveWindow(hTree, rcTree, False)
End Sub
Private Sub _centerTo(hDlg As IntPtr, hRef As IntPtr)
Dim rcDlg As Win32.RECT
Win32.GetWindowRect(hDlg, rcDlg)
Dim rcRef As Win32.RECT
Win32.GetWindowRect(hRef, rcRef)
Dim cx As Integer = (rcRef.Width - rcDlg.Width) / 2
Dim cy As Integer = (rcRef.Height - rcDlg.Height) / 2
Dim rcNew As New Win32.RECT(rcRef.Left + cx, rcRef.Top + cy, rcDlg.Width, rcDlg.Height)
Win32.MoveWindow(hDlg, rcNew, True)
End Sub
End Class
End Namespace
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I see two issues with the above dialogboxes (and any other dialog I've seen):
1: You cannot specify a custom start folder which will be preselected when the dialogbox opens, let's say "c:\temp"
2: When you type a path in the textbox and push TAB or ENTER this should NOT be seen as the final selected folder, but the treeview should instead move and expand to that path (just as if you did the same in Windows Explorer).
(sorry for putting this as an answer, cannot make a comment)