I work with a relay module that I normaly connect via USB. That all works perfectly. Now I would like to connect it via the network. All manufacturer's VB.NET code works in vba except for accessing this module over the network.
Public Declare PtrSafe Function DapiOpenModuleEx Lib "DELIB64" (ByVal moduleID As Long, ByVal nr As Long, ByRef exbuffer As DAPI_OPENMODULEEX_STRUCT, ByVal open_options As Long) As Long
' Definitions for DapiOpenEx
Public Type DAPI_OPENMODULEEX_STRUCT
address(255) As Byte
timeout As Long
portno As Long
encryption_type As Long
encryption_password(31) As Byte
End Type
'Open ETH-Module with parameter
Dim handle as Ulong
Dim MyModuleID As UInt32
MyModuleID = 42
Dim open_buffer As New DELib64.DAPI_OPENMODULEEX_STRUCT
open_buffer.address = System.String.Copy(192.168.1.1 As String) As String
open_buffer.portno = 0
handle = DELib.DapiOpenModuleEx(MyModuleID, 0, open_buffer)
I am getting an error "open_buffer.address = System.String.Copy(192.168.1.1 As String) As String "
Can someone help me with what i need to change here?
Dim handle as LongLong
Dim MyModuleID As Long
MyModuleID = 42
Dim open_buffer As Delib64.DAPI_OPENMODULEEX_STRUCT
open_buffer.address = system.String.Copy("192.168.1.1" AS String) As String
open_buffer.portno = 0
handle1 = DapiOpenModuleEx(MyModuleID, 0, open_buffer, 0)
According to your comment, the original line of code is
strcpy((char*) open_buffer.address, "192.168.1.10");
So you need to copy the ASCII (single-byte) string "192.168.1.10" into a VBA byte array. This is surprisingly hard, since the obvious approach of open_buffer.address = StrConv("192.168.1.10", vbFromUnicode) won't work (you can't assign to a fixed-size array that's part of a type).
One obvious solution would be to make a Windows API call to CopyMemory, but if we want a VBA-only solution, a simple loop should suffice:
Dim i As Long
Dim b() As Byte
b = StrConv("192.168.1.10", vbFromUnicode)
For i = 0 To UBound(b)
open_buffer.address(i) = b(i)
Next
open_buffer.address(UBound(b) + 1) = 0 ' C-strings need to be 0-terminated
(I do have the feeling that this should be easier, so I'll gladly upvote competing, simpler answers.)
Has anyone used VB.NET to get face recognition data from a Dahua NVR using VB.NET?
I am facing two problems that I just can't figure out.
I can connect to the NVR and set up a callback for video using
bDeviceInitialized = CLIENT_Init(AddressOf DeviceDisconnected, 0)
Dim lSDKVersion As Long
lSDKVersion = CLIENT_GetSDKVersion()
console.writeline( "SDK: " + lSDKVersion.ToString.Substring(0, 1) + "." + lSDKVersion.ToString.Substring(1, 2) + " " + lSDKVersion.ToString.Substring(3) )
fAnalyzer = AddressOf AnalyzerDataCallBack
'Set reconnect callback
CLIENT_SetAutoReconnect(AddressOf DeviceReconnected, 0)
' Set device connection timeout And trial times.
' Optional operation
Dim nWaitTime As Integer = 5000 ' Timeout Is 5 seconds.
Dim nTryTimes As Integer = 3 ' If timeout, it will try to log in three times.
CLIENT_SetConnectTime(nWaitTime, nTryTimes)
'A wait is required
System.Threading.Thread.Sleep(1000)
netInLoginWithHighLevelSecurity.dwSize = Marshal.SizeOf(netInLoginWithHighLevelSecurity)
Array.Copy(System.Text.Encoding.Default.GetBytes(My.Settings.DeviceIP), netInLoginWithHighLevelSecurity.szIP, My.Settings.DeviceIP.Length)
netInLoginWithHighLevelSecurity.nPort = CInt(My.Settings.DevicePort)
Array.Copy(System.Text.Encoding.Default.GetBytes(My.Settings.DeviceUserId), netInLoginWithHighLevelSecurity.szUserName, My.Settings.DeviceUserId.Length)
Array.Copy(System.Text.Encoding.Default.GetBytes(My.Settings.DevicePassword), netInLoginWithHighLevelSecurity.szPassword, My.Settings.DevicePassword.Length)
netInLoginWithHighLevelSecurity.emSpecCap = EM_LOGIN_SPAC_CAP_TYPE.EM_LOGIN_SPEC_CAP_TCP
netOutLoginWithHighLevelSecurity.stuDeviceInfo = devInfo
netOutLoginWithHighLevelSecurity.dwSize = Marshal.SizeOf(netOutLoginWithHighLevelSecurity)
'Create a pointer for the structure
'pNetOutLoginWithHighLevelSecurity = Marshal.AllocHGlobal(Marshal.SizeOf(netOutLoginWithHighLevelSecurity))
hLoginId = CLIENT_LoginWithHighLevelSecurity(netInLoginWithHighLevelSecurity, netOutLoginWithHighLevelSecurity)
' Get the serial number of the NVR
Dim i As Integer = 0
Dim strSerial As String = ""
While i < 64 And netOutLoginWithHighLevelSecurity.stuDeviceInfo.sSerialNumber(i) <> 0
strSerial &= Chr(netOutLoginWithHighLevelSecurity.stuDeviceInfo.sSerialNumber(i))
i += 1
End While
' Enable cameras
Dim dwUser As Int64 = 0
Dim oReserved As IntPtr = 0
Dim nChannel As Int16 =0
Dim iNeedPicture As Int32 = 1
' pbChannel1 is a PictureBox
lMonitorChannel(nChannel) = CLIENT_RealPlayEx(hLoginId, nChannel, pbChannel1.Handle, EM_REAL_PLAY_TYPE.EM_REAL_PLAY_REALPLAY)
lAlarmFaceDetection(nChannel) = CLIENT_RealLoadPictureEx(hLoginId, nChannel, EVENT_IVS_ALL, iNeedPicture, fAnalyzer, Nothing, Nothing)
This works fine and I can see the video from channel 1.
The problems are in the analyzer callback which is defined as
Public Delegate Sub AnalyzerDataCallBackDelegate(lAnalyzerHandle As Int64, dwAlarmType As UInt32, AlarmInfo As IntPtr, pBuffer As IntPtr, dwBufferSize As UInt32, dwUser As Int64, nSequence As Int16, Reserved As IntPtr)
Public Shared Sub AnalyzerDataCallBack(ByVal lAnalyzerHandle As Int64, ByVal dwAlarmType As Int32, ByVal AlarmInfo As IntPtr,
ByVal pBuffer As IntPtr, ByVal dwBufferSize As Int32, ByVal dwUser As Int64, ByVal nSequence As Int16,
ByVal Reserved As IntPtr)
Firstly, I am not getting any event other than motion detect and face recognition, even though I subscribed to EVENT_IVS_ALL.
Secondly, I am not getting complete face recognition information.
I copied from the unmanaged buffer into a (complex) structure.
structFaceRecognitionInfo = CType(Marshal.PtrToStructure(AlarmInfo, GetType(DEV_EVENT_FACERECOGNITION_INFO)), DEV_EVENT_FACERECOGNITION_INFO)
But I don't get complete information. Only the first few elements are filled with the rest have garbage or zeros.
I tried copying the buffer into a byte array to inspect the data during debug and see that it is indeed filled with zeros.
Dim lenBuffer As Int32 = Marshal.SizeOf(Of DEV_EVENT_FACERECOGNITION_INFO)
ReDim bData(lenBuffer)
Dim gchBuffer As GCHandle = GCHandle.Alloc(bData, GCHandleType.Pinned)
Marshal.Copy(AlarmInfo, bData, 0, lenBuffer)
gchBuffer.Free()
I've been stuck at this point for a week.
I have a DLL with the following function and is being used in my application
WritetoBuffer(BYTE* pBuffer, DATA_TYPE Type);
This is the code being used in VB 6
Dim pBuffer() as byte
ReDim pBuffer(0 To (300 * 400 * 3 - 1))
Dim ppBuf As Long
ppBuf = VarPtr(pImageBuffer(0))
Dim Rtn As Integer
Rtn = WritetoBuffer(ppBuf, 1)
I am trying to write the equivalent code in VB.NET, but I am facing difficulties in it. Tried using the following function, but it's not working.
Public Function VarPtr(ByVal e As Object) As Intptr
Dim GC As GCHandle = GCHandle.Alloc(e, GCHandleType.Pinned)
Dim GC2 As Intptr = GC.AddrOfPinnedObject.ToInt32
GC.Free()
Return GC2
End Function
I haven't used Marshal Class or similar functions before and I am not sure about the right way to do it. Can someone please advice me on this?
As #Dai commented, .ToInt32 is incorrect here, and you can’t free the handle before you use it.
Dim pBuffer(300 * 400 * 3 - 1) As Byte
Dim pinned = GCHandle.Alloc(pBuffer, GCHandleType.Pinned)
Dim Rtn As Integer = WritetoBuffer(pinned.AddrOfPinnedObject(), 1)
pinned.Free()
Try this. You need GCHandle to stay alive while you make your call. Just returning the address of the pointer is not enough from what I understand. When you're done then free the handle.
Dim Handle As GCHandle = GCHandle.Alloc(pBuffer, GCHandleType.Pinned)
Dim ppbuf As IntPtr = Handle.AddrOfPinnedObject.ToInt32
Dim Rtn As Integer
Rtn = WritetoBuffer(ppbuf, 1)
Handle.Free()
In cases such as this you shouldn't need to get a pointer of your byte array. Due to the fact that since BYTE* pBuffer is used as an array, that is all you need it to be in VB.NET as well.
Thus you could declare your P/Invoke like this:
<DllImport("yourfile.dll")> _
Public Shared Function WritetoBuffer(ByVal pBuffer As Byte(), ByVal Type As Integer) As Integer
End Function
...and then use it like this:
Dim pBuffer() as byte
ReDim pBuffer(0 To (300 * 400 * 3 - 1))
Dim Rtn As Integer = WritetoBuffer(pBuffer, 1)
I am using the following code
This error occurs :
Attempted to read or write protected memory. This is often an indication that other memory is corrupted. Attempted to read or write to protected memory. This is often an indication that other memory is corrupted.
Public Function PadBytes(abData() As Byte) As Object
Dim nLen As Long
Dim nPad As Integer
Dim abPadded() As Byte
Dim i As Long
'Set up error handler for empty array
On Error GoTo ArrayIsEmpty
nLen = UBound(abData) - LBound(abData) + 1
nPad = ((nLen \ 8) + 1) * 8 - nLen
ReDim Preserve abPadded(nLen + nPad - 1) ' Pad with # of pads (1-8)
If nLen > 0 Then
CopyMemory(abPadded(0), abData(0), nLen)
End If
For i = nLen To nLen + nPad - 1
abPadded(i) = CByte(nPad)
Next
ArrayIsEmpty:
PadBytes = abPadded
End Function
Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Byte, Source As Byte, ByVal Length As Long)
Please show me the right way.
I think you might need to do the copy like the following
CopyMemory(abPadded(0), byval abData(0), nLen)
I don't have VB6 any more so you'd need to try it for your self. Fingers crossed it works.
I'm working in VB.NET and having some issues with a POS Printer I just connected (Epson TM-T88V). I recently downloaded a sample code from something I found on YouTube that used an Epson TM-88II, an older model of the V. This code would work perfectly fine if I could just open the serial port! What's happening is that the printer is on port USB-001 (the virtual printer port) and you can't just set that as your COM Port in VB to write to it. I downloaded the Microsoft POS for .NET and the OPOSN from Epson. The only question I have so far is where do I even start? Can anyone help me with connecting to the printer with VB and then maybe move into sending a basic "Hello World" to the printer followed by an autocut?
This is hard since it is not easy to find good articles. If you look for information you will notice how epson is not really happy sharing their knowleage. bot here are some articles that helped me with this:
this article is really good if you want to print images Images
This one is from epson Epson
** Update **
this is what makes the magic:
Public Class EscPOS
Private Shared PrintNam As String = "POS"
Public Shared Property PrinterName
Set(value)
PrintNam = value
End Set
Get
Return PrintNam
End Get
End Property
' Structure and API declarions:
<StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Unicode)> _
Structure DOCINFOW
<MarshalAs(UnmanagedType.LPWStr)> Public pDocName As String
<MarshalAs(UnmanagedType.LPWStr)> Public pOutputFile As String
<MarshalAs(UnmanagedType.LPWStr)> Public pDataType As String
End Structure
<DllImport("winspool.Drv", EntryPoint:="OpenPrinterW", _
SetLastError:=True, CharSet:=CharSet.Unicode, _
ExactSpelling:=True, CallingConvention:=CallingConvention.StdCall)> _
Public Shared Function OpenPrinter(ByVal src As String, ByRef hPrinter As IntPtr, ByVal pd As Long) As Boolean
End Function
<DllImport("winspool.Drv", EntryPoint:="ClosePrinter", _
SetLastError:=True, CharSet:=CharSet.Unicode, _
ExactSpelling:=True, CallingConvention:=CallingConvention.StdCall)> _
Public Shared Function ClosePrinter(ByVal hPrinter As IntPtr) As Boolean
End Function
<DllImport("winspool.Drv", EntryPoint:="StartDocPrinterW", _
SetLastError:=True, CharSet:=CharSet.Unicode, _
ExactSpelling:=True, CallingConvention:=CallingConvention.StdCall)> _
Public Shared Function StartDocPrinter(ByVal hPrinter As IntPtr, ByVal level As Int32, ByRef pDI As DOCINFOW) As Boolean
End Function
<DllImport("winspool.Drv", EntryPoint:="EndDocPrinter", _
SetLastError:=True, CharSet:=CharSet.Unicode, _
ExactSpelling:=True, CallingConvention:=CallingConvention.StdCall)> _
Public Shared Function EndDocPrinter(ByVal hPrinter As IntPtr) As Boolean
End Function
<DllImport("winspool.Drv", EntryPoint:="StartPagePrinter", _
SetLastError:=True, CharSet:=CharSet.Unicode, _
ExactSpelling:=True, CallingConvention:=CallingConvention.StdCall)> _
Public Shared Function StartPagePrinter(ByVal hPrinter As IntPtr) As Boolean
End Function
<DllImport("winspool.Drv", EntryPoint:="EndPagePrinter", _
SetLastError:=True, CharSet:=CharSet.Unicode, _
ExactSpelling:=True, CallingConvention:=CallingConvention.StdCall)> _
Public Shared Function EndPagePrinter(ByVal hPrinter As IntPtr) As Boolean
End Function
<DllImport("winspool.Drv", EntryPoint:="WritePrinter", _
SetLastError:=True, CharSet:=CharSet.Unicode, _
ExactSpelling:=True, CallingConvention:=CallingConvention.StdCall)> _
Public Shared Function WritePrinter(ByVal hPrinter As IntPtr, ByVal pBytes As IntPtr, ByVal dwCount As Int32, ByRef dwWritten As Int32) As Boolean
End Function
Public Shared Function PrintImage(BM As Bitmap) As Boolean
Dim b As Byte() = ConvertImagetoBytes(BM)
Dim bSuccess As Boolean
Dim pUnmanagedBytes As IntPtr
' Allocate some unmanaged memory for those bytes.
pUnmanagedBytes = Marshal.AllocCoTaskMem(b.Count)
' Copy the managed byte array into the unmanaged array.
Marshal.Copy(b, 0, pUnmanagedBytes, b.Count)
' Send the unmanaged bytes to the printer.
bSuccess = EscPOS.PrintBytes(b)
Return bSuccess
End Function
Public Shared Function PrintBytes(Document As Byte()) As Boolean
Dim hPrinter As IntPtr ' The printer handle.
Dim dwError As Int32 ' Last error - in case there was trouble.
Dim di As DOCINFOW ' Describes your document (name, port, data type).
Dim dwWritten As Int32 ' The number of bytes written by WritePrinter().
Dim bSuccess As Boolean ' Your success code.
' Set up the DOCINFO structure.
di = New DOCINFOW
di.pDocName = "RAW LOGO"
di.pDataType = "RAW"
hPrinter = New IntPtr(0)
bSuccess = False
If OpenPrinter(PrinterName.Normalize(), hPrinter, 0) Then
If StartDocPrinter(hPrinter, 1, di) Then
Dim managedData As Byte()
Dim unmanagedData As IntPtr
managedData = Document
unmanagedData = Marshal.AllocCoTaskMem(managedData.Length)
Marshal.Copy(managedData, 0, unmanagedData, managedData.Length)
If StartPagePrinter(hPrinter) Then
bSuccess = WritePrinter(hPrinter, unmanagedData, managedData.Length, dwWritten)
EndPagePrinter(hPrinter)
End If
Marshal.FreeCoTaskMem(unmanagedData)
EndDocPrinter(hPrinter)
End If
ClosePrinter(hPrinter)
End If
If bSuccess = False Then
dwError = Marshal.GetLastWin32Error()
End If
Return bSuccess
End Function
Public Shared Function ConvertImagetoBytes(BM As Bitmap) As Byte()
Dim Data As BitMapData = GetBitmapData(BM)
Dim Op As New MemoryStream
Dim bw As New BinaryWriter(Op)
bw.Write(Chr(Keys.Escape))
bw.Write("#"c)
' So we have our bitmap data sitting in a bit array called "dots."
' This is one long array of 1s (black) and 0s (white) pixels arranged
' as if we had scanned the bitmap from top to bottom, left to right.
' The printer wants to see these arranged in bytes stacked three high.
' So, essentially, we need to read 24 bits for x = 0, generate those
' bytes, and send them to the printer, then keep increasing x. If our
' image is more than 24 dots high, we have to send a second bit image
' command to draw the next slice of 24 dots in the image.
' Set the line spacing to 24 dots, the height of each "stripe" of the
' image that we're drawing. If we don't do this, and we need to
' draw the bitmap in multiple passes, then we'll end up with some
' whitespace between slices of the image since the default line
' height--how much the printer moves on a newline--is 30 dots.
bw.Write(Chr(Keys.Escape))
bw.Write("3"c)
' '3' just means 'change line height command'
bw.Write(CByte(24))
' OK. So, starting from x = 0, read 24 bits down and send that data
' to the printer. The offset variable keeps track of our global 'y'
' position in the image. For example, if we were drawing a bitmap
' that is 48 pixels high, then this while loop will execute twice,
' once for each pass of 24 dots. On the first pass, the offset is
' 0, and on the second pass, the offset is 24. We keep making
' these 24-dot stripes until we've run past the height of the
' bitmap.
Dim offset As Integer = 0
Dim width As Byte()
While offset < Data.Height
' The third and fourth parameters to the bit image command are
' 'nL' and 'nH'. The 'L' and the 'H' refer to 'low' and 'high', respectively.
' All 'n' really is is the width of the image that we're about to draw.
' Since the width can be greater than 255 dots, the parameter has to
' be split across two bytes, which is why the documentation says the
' width is 'nL' + ('nH' * 256).
bw.Write(Chr(Keys.Escape))
bw.Write("*"c)
' bit-image mode
bw.Write(CByte(33))
' 24-dot double-density
width = BitConverter.GetBytes(Data.Width)
bw.Write(width(0))
' width low byte
bw.Write(width(1))
' width high byte
For x As Integer = 0 To Data.Width - 1
' Remember, 24 dots = 24 bits = 3 bytes.
' The 'k' variable keeps track of which of those
' three bytes that we're currently scribbling into.
For k As Integer = 0 To 2
Dim slice As Byte = 0
' A byte is 8 bits. The 'b' variable keeps track
' of which bit in the byte we're recording.
For b As Integer = 0 To 7
' Calculate the y position that we're currently
' trying to draw. We take our offset, divide it
' by 8 so we're talking about the y offset in
' terms of bytes, add our current 'k' byte
' offset to that, multiple by 8 to get it in terms
' of bits again, and add our bit offset to it.
Dim y As Integer = (((offset \ 8) + k) * 8) + b
' Calculate the location of the pixel we want in the bit array.
' It'll be at (y * width) + x.
Dim i As Integer = (y * Data.Width) + x
' If the image (or this stripe of the image)
' is shorter than 24 dots, pad with zero.
Dim v As Boolean = False
If i < Data.Dots.Length Then
v = Data.Dots(i)
End If
' Finally, store our bit in the byte that we're currently
' scribbling to. Our current 'b' is actually the exact
' opposite of where we want it to be in the byte, so
' subtract it from 7, shift our bit into place in a temp
' byte, and OR it with the target byte to get it into there.
slice = slice Or CByte((If(v, 1, 0)) << (7 - b))
Next
' Phew! Write the damn byte to the buffer
bw.Write(slice)
Next
Next
' We're done with this 24-dot high pass. Render a newline
' to bump the print head down to the next line
' and keep on trucking.
offset = offset + 24
bw.Write(vbCrLf.ToCharArray)
End While
' Restore the line spacing to the default of 30 dots.
bw.Write(Chr(Keys.Escape))
bw.Write("3"c)
bw.Write(CByte(30))
bw.Flush()
Return Op.ToArray
End Function
Private Shared Function GetBitmapData(BM As Bitmap) As BitMapData
Dim threshold = 127
Dim index As Integer = 0
Dim dimensions As Integer = BM.Width * BM.Height
Dim dots As BitArray = New BitArray(dimensions)
Dim res As New BitMapData
Dim a As Integer
For y = 0 To BM.Height - 1
For x = 0 To BM.Width - 1
Dim col As Color = BM.GetPixel(x, y)
Dim luminance = CInt(col.R * 0.3 + col.G * 0.59 + col.B * 0.11)
If (luminance < threshold) = True Then
a = 1
End If
dots(index) = (luminance < threshold)
index = index + 1
Next
Next
res.Dots = dots : res.Height = BM.Height : res.Width = BM.Width
Return res
End Function
Private Class BitMapData
Public Dots As BitArray
Public Height As Int16
Public Width As Int16
End Class
' When the function is given a printer name and an unmanaged array of
' bytes, the function sends those bytes to the print queue.
' Returns True on success or False on failure.
Private Shared Function PrintEsto(ByVal pBytes As IntPtr, ByVal dwCount As Int32) As Boolean
Dim hPrinter As IntPtr ' The printer handle.
Dim dwError As Int32 ' Last error - in case there was trouble.
Dim di As DOCINFOW = Nothing ' Describes your document (name, port, data type).
Dim dwWritten As Int32 ' The number of bytes written by WritePrinter().
Dim bSuccess As Boolean ' Your success code.
' Set up the DOCINFO structure.
With di
.pDocName = "RAW Document"
.pDataType = "RAW"
End With
' Assume failure unless you specifically succeed.
bSuccess = False
If OpenPrinter(PrinterName, hPrinter, 0) Then
If StartDocPrinter(hPrinter, 1, di) Then
If StartPagePrinter(hPrinter) Then
' Write your printer-specific bytes to the printer.
bSuccess = WritePrinter(hPrinter, pBytes, dwCount, dwWritten)
EndPagePrinter(hPrinter)
End If
EndDocPrinter(hPrinter)
End If
ClosePrinter(hPrinter)
End If
' If you did not succeed, GetLastError may give more information
' about why not.
If bSuccess = False Then
dwError = Marshal.GetLastWin32Error()
End If
Return bSuccess
End Function
' SendFileToPrinter()
' When the function is given a file name and a printer name,
' the function reads the contents of the file and sends the
' contents to the printer.
' Presumes that the file contains printer-ready data.
' Shows how to use the SendBytesToPrinter function.
' Returns True on success or False on failure.
Public Shared Function PrintFile(ByVal szFileName As String) As Boolean
' Open the file.
Try
Dim fs As New FileStream(szFileName, FileMode.Open)
' Create a BinaryReader on the file.
Dim br As New BinaryReader(fs)
' Dim an array of bytes large enough to hold the file's contents.
Dim bytes(fs.Length) As Byte
Dim bSuccess As Boolean
' Your unmanaged pointer.
Dim pUnmanagedBytes As IntPtr
' Read the contents of the file into the array.
bytes = br.ReadBytes(fs.Length)
' Allocate some unmanaged memory for those bytes.
pUnmanagedBytes = Marshal.AllocCoTaskMem(fs.Length)
' Copy the managed byte array into the unmanaged array.
Marshal.Copy(bytes, 0, pUnmanagedBytes, fs.Length)
' Send the unmanaged bytes to the printer.
bSuccess = PrintEsto(pUnmanagedBytes, fs.Length)
' Free the unmanaged memory that you allocated earlier.
Marshal.FreeCoTaskMem(pUnmanagedBytes)
fs.Close()
Return bSuccess
Catch ex As Exception
MsgBox(ex.Message)
Return False
End Try
End Function
' When the function is given a string and a printer name,
' the function sends the string to the printer as raw bytes.
Public Shared Function PrintString(ByVal szString As String)
Dim pBytes As IntPtr
Dim dwCount As Int32
Dim Res As Boolean
' How many characters are in the string?
dwCount = szString.Length()
' Assume that the printer is expecting ANSI text, and then convert
' the string to ANSI text.
pBytes = Marshal.StringToCoTaskMemAnsi(szString)
' Send the converted ANSI string to the printer.
Res = PrintEsto(pBytes, dwCount)
Marshal.FreeCoTaskMem(pBytes)
Return Res
End Function
End Class
And this is how I call whit class:
If EsImpresionTermica Then
If File.Exists(My.Application.Info.DirectoryPath & "\Settings.{2559a1f2-21d7-11d4-bdaf-00c04f60b9f0}\Logo.conf") Then _
RawPrinting.EscPOS.PrintBytes(File.ReadAllBytes(My.Application.Info.DirectoryPath & "\Settings.{2559a1f2-21d7-11d4-bdaf-00c04f60b9f0}\Logo.conf"))
Else
Dim MSe As New MemoryStream
Dim BWe As New BinaryWriter(MSe)
BWe.Write(Chr(&H1B))
BWe.Write("#"c) 'Inicia Imresora
BWe.Write(Chr(&H1B))
BWe.Write(CByte(3))
BWe.Write(Chr(18)) 'Establece interlineado
BWe.Write(Chr(&H1B))
BWe.Write("U"c)
BWe.Write(Chr(1)) 'Impresión unidireccional
BWe.Write(Chr(&H1B))
BWe.Write("a"c)
BWe.Write(Chr(1)) 'Centra Impresión
BWe.Write(Chr(&H1B))
BWe.Write(vbCrLf.ToCharArray)
BWe.Write(Encoding.ASCII.GetBytes(Encabezado))
BWe.Write(Chr(10))
BWe.Write(Chr(10))
BWe.Flush()
BWe.Close()
RawPrinting.EscPOS.PrintBytes(MSe.ToArray)
End If
End Sub