I am attempting to get the filepath of an image that is dropped onto a button in VB. I have set the button to allow drop and I have set up this segment to hold the event code:
Private Sub btnDropZone_drop(sender As Object, e As EventArgs) Handles btnDropZone.DragDrop
End Sub
How would I go about getting the filepath from this event as a string? Thanks in advance!
A button is a pretty small drop target, but it would work the same as anything else: examine e As DragEventArgs:
Private Sub btnDropZone_drop(sender As Object,
e As EventArgs) Handles btnDropZone.DragDrop
'ToDo check the format to see what was dropped
Dim Files As String() = CType(e.Data.GetData(DataFormats.FileDrop), String())
For Each s As String In Files
ListBox1.Items.Add(Path.GetFileName(s))
Next
End Sub
When you are trying to figure out what to do in an event, always look up the meaning and contents of the eventargs
Related
I have written some code to create a PictureBox every time the code runs, which works fine.
Public Sub BtnHit_Click(sender As Object, e As EventArgs) Handles BtnHit.Click
Dim PicBoxNewCard As New PictureBox
PicBoxNewCard.Width = 114
PicBoxNewCard.Height = 166
PicBoxNewCard.SizeMode = PictureBoxSizeMode.Zoom
DrawCard(PicBoxNewCard)
Me.Controls.Add(PicBoxNewCard)
PicBoxNewCard.Location = New Point((257 + (57 * DrawnCardCounter)), 349)
But I want to be able to delete these created PictureBoxes by pressing a button, which would be in a different sub to the one that creates the Boxes.
I have googled around and have found references to creating Classes, Panels etc and have not had any success. I have found the exact code that I need to make it work, (Me.Controls.Remove(PicBoxNewCard)) but it only seems to work when executed in the same Sub.
Set the Name or Tag property and use that later when searching for the PictureBox to remove.
PicBoxNewCard.Name = $"Card{DrawnCardCounter}"
Private Sub RemoveButton_Click(sender As Object, e As EventArgs) Handles RemoveButton.Click
RemoveCardPicBox(10)
End Sub
Private Sub RemoveCardPicBox(CardNumber As Integer)
Dim delpicBox As PictureBox = Me.Controls.OfType(Of PictureBox).Where(Function(x) x.Name = $"Card{CardNumber}").FirstOrDefault
If Not delpicBox Is Nothing Then
Me.Controls.Remove(delpicBox)
End If
End Sub
I'm new to this site and also a newbee in vb.net, I created a simple form in vb.net, a form with 3 buttons, by clicking Button1 Species1.txt is created, and by clicking Button2 the lines in Species1.txt are copied in a String Array called astSpecies(), and by Button3 the String Array is copied in a new file, named Species2.txt, below is the code.
Public Class Form4
Dim astSpecies() As String
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim myStreamWriter = New StreamWriter("C:\Users\Administrator\Documents\species1.txt", True)
myStreamWriter.WriteLine("Pagasius pangasius")
myStreamWriter.WriteLine("Meretrix lyrata")
myStreamWriter.WriteLine("Psetta maxima")
myStreamWriter.WriteLine("Nephrops norvegicus")
myStreamWriter.WriteLine("Homarus americanus")
myStreamWriter.WriteLine("Procambarus clarkii")
myStreamWriter.Close()
MsgBox("list complete")
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
Dim myStreamReader = New StreamReader("C:\Users\Administrator\Documents\species1.txt")
Dim i As Integer
Dim stOutput As String
stOutput = ""
Do While Not myStreamReader.EndOfStream
astSpecies(i) = myStreamReader.ReadLine
stOutput = stOutput & astSpecies(i) & vbNewLine
i = i + 1
Loop
myStreamReader.Close()
MsgBox(stOutput)
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
Dim myStreamWriter = New StreamWriter("C:\Users\Administrator\Documents\species2.txt", True)
Dim o As Integer
Do While o <= astSpecies.Length
myStreamWriter.WriteLine(astSpecies(o))
o = o + 1
Loop
myStreamWriter.Close()
End Sub
End Class
First of all, you should make a few settings when it comes to VB.Net. 1.) set Option Strict to On 2.) remove the VB6 namespace. VB6 is the old Visual Basic. There are many functions in this that are inefficient from today's perspective. So please do not write MsgBox() but MessageBox.Show("").
(If you still need control characters such as NewLine or Tab, you can set a selective reference with Imports Microsoft.VisualBasic.ControlChars. Sounds contradictory, but it is useful, because why should you also write ChrW(9), it is not legible.)
I quickly started a project myself and wrote whatever you wanted.
I still don't quite understand why you first write things into a text file, then read them out, and then write that into a second text file – I want to say: where do the strings originally come from? The strings must have been there already? Anyway, I filled a List(of String) in the Button2_Click procedure. This has the advantage that you don't have to know in advance how many strings are coming, and you can sort them later and so on ...
You should also discard all Writers when you no longer need them. So use Using. Otherwise it can happen that the written files are not discarded and you can no longer edit the file.
Imports Microsoft.VisualBasic.ControlChars
Imports Microsoft.WindowsAPICodePack.Dialogs
Public NotInheritable Class FormMain
Private Path As String = ""
Private allLines As New List(Of String)
Private Sub FormMain_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Me.BackColor = Color.FromArgb(161, 181, 165)
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Using OFolderD As New CommonOpenFileDialog
OFolderD.Title = "Ordner auswählen"
OFolderD.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.Desktop)
OFolderD.IsFolderPicker = True
If OFolderD.ShowDialog() = CommonFileDialogResult.Ok Then
Path = OFolderD.FileName
Else
Return
End If
End Using
Path &= "\Data.txt"
Using txtfile As System.IO.StreamWriter = My.Computer.FileSystem.OpenTextFileWriter(Path, True)
txtfile.WriteLine("Pagasius pangasius")
txtfile.WriteLine("Meretrix lyrata")
txtfile.WriteLine("Psetta maxima")
txtfile.WriteLine("Nephrops norvegicus")
txtfile.WriteLine("Homarus americanus")
txtfile.WriteLine("Procambarus clarkii")
txtfile.Close()
End Using
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
'read all Text
Dim RAT() As String = System.IO.File.ReadAllLines(Path, System.Text.Encoding.UTF8)
If RAT.Length = 0 OrElse RAT.Length = 1 Then
MessageBox.Show("The File only contains 0 or 1 characters.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Hand)
Return
End If
allLines.AddRange(RAT)
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
Dim Pfad_txt As String = Path.Substring(0, Path.LastIndexOf("\"c)) & "\Data2.txt"
Using txtfile As System.IO.StreamWriter = My.Computer.FileSystem.OpenTextFileWriter(Pfad_txt, True)
For Each Line As String In allLines
txtfile.WriteLine(Line)
Next
txtfile.Close()
End Using
End Sub
End Class
By the way: I use a FolderBrowserDialog in the Button1_Click procedure. This should be done so that the program also runs properly on other PCs. In order to be able to use the FBD, you have to download Microsoft.WindowsAPICodePack.Dialogs in Visual Studio's own Nuget package manager.
how to set Option Strict to On
How to uncheck VB6.
how to install FolderBrowserDialog in Visual Studio
Button1
If you want to use a StreamWriter it should be disposed. Classes in the .net Framework that have a Dispose method may use resources outside of the framework which need to be cleaned up. The classes shield you from these details by provided a Dispose method which must be called to properly do the clean up. Normally this is done with Using blocks.
I used a string builder which saves creating and throwing away a string each time you change the string. You may have heard that strings are immutable (cannot be changed). The StringBuilder class gets around this limitation. It is worth using if you have many changes to your string.
The File class is a .net class that you can use to read or write files. It is not as flexible as the stream classes but it is very easy to use.
Button 2
When you declared your Array, you declared an array with no elements. You cannot add elements to an array with no space for them. As Daniel pointed out, you can use the .net class List(Of T) The T stands for Type. This is very good suggestion when you don't know the number of elements in advance. I stuck with the array idea by assigning the array returned by File.ReadAllLines to the lines variable.
You get the same result by simply reading all the text and displaying it.
Button 3
Again I used the File class here which allows you to complete your task in a single line of code. Using 2 parameters for the String.Join method, the separator string and the array to join, we reproduce the original file.
Private SpeciesPath As String = "C:\Users\maryo\Documents\species1.txt"
Private lines As String()
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim sb As New StringBuilder
sb.AppendLine("Pagasius pangasius")
sb.AppendLine("Meretrix lyrata")
sb.AppendLine("Psetta maxima")
sb.AppendLine("Nephrops norvegicus")
sb.AppendLine("Homarus americanus")
sb.AppendLine("Procambarus clarkii")
File.WriteAllText(SpeciesPath, sb.ToString)
MsgBox("list complete")
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
lines = File.ReadAllLines(SpeciesPath)
MessageBox.Show(String.Join(Environment.NewLine, lines))
'OR
MessageBox.Show(File.ReadAllText(SpeciesPath))
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
File.WriteAllLines("C:\Users\maryo\Documents\species2.txt", lines))
End Sub
Good day!
I want to add some strings from a barcode scanner, captured in a text box, to a list box, and, before adding it, to check if the specific string hasn't been already added. So I have a text box called txtWO which captures what the reader scans and a list box called lstScanBOM to which I add the text box string if the item is not already added. The problem is, that whatever I do, only after the specific string is added twice the checking for duplicate entry starts to work. In other words I scan the same string twice, it added it, and then when I scan the third time only it throws the message with the error saying it is a duplicate. I don't understand why is doing this. The code is below:
Private Sub frmValidareFIP_Load(sender As Object, e As EventArgs) Handles MyBase.Load
If txtWO.Focused = False Then
txtWO.Select()
End If
End Sub
Private Sub AddUnique(StringToAdd As String)
If lstScanBom.Items.Contains(StringToAdd) = True Then
MsgBox("Articol duplicat!", vbOKOnly)
Else
'it does not exist, so add it..
lstScanBom.Items.Add(StringToAdd)
End If
End Sub
Private Sub txtWO_KeyDown(ByVal sender As Object,ByVal e As System.Windows.Forms.KeyEventArgs) Handles txtWO.KeyDown
If e.KeyCode = Keys.Enter Then
Dim barcode As String
barcode = txtWO.Text
AddUnique(barcode)
txtWO.Clear()
txtWO.Focus()
End If
End Sub
IMO Try listing the data outside of the ListBox. I can't see why it isn't working, maybe we need a third pair of eyes to see it!?
Try adding a list (of string) as a Private within the form, populate this as your user scans, and check the duplicate there..
This is definately not the best solution, but I'm sure it will help!
Private List_Barcodes As List(Of String)
Private Sub frmValidareFIP_Load(sender As Object, e As EventArgs) Handles MyBase.Load
List_Barcodes = New List(Of String)
'You can also populate this list on load, if you have a stored cahce of previous scanned barcodes?
'List_Barcodes.Add("0123456")
'List_Barcodes.Add("4567890")
'...etc
If txtWO.Focused = False Then
txtWO.Select()
End If
End Sub
Private Sub AddUnique(StringToAdd As String)
If List_Barcodes.Contains(StringToAdd) Then
MsgBox("Articol duplicat!", vbOKOnly)
Else
'Place into dynamic list
List_Barcodes.Add(StringToAdd)
'and Place into your listbox
lstScanBom.Items.Add(StringToAdd)
End If
End Sub
Private Sub txtWO_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles txtWO.KeyDown
If e.KeyCode = Keys.Enter Then
Dim barcode As String
barcode = txtWO.Text
AddUnique(barcode)
txtWO.Clear()
txtWO.Focus()
End If
End Sub
Your barcode reader is returning <carriage return><line feed> as enter. Your code catches the enter key (carriage return = 13), but leaves the line feed (10) character. So the next time you scan something it will start with a line feed. The two strings in your example are different because the first is "58335001" and the second is "<line feed>58335001". The third one is "<line feed>58335001", which is a duplicate of the second.
One way to fix this is to trim your string.
Private Sub txtWO_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles txtWO.KeyDown
If e.KeyCode = Keys.Enter Then
Dim barcode As String
'Add the .Trim() to remove the leading <line feed> character
barcode = txtWO.Text.Trim()
AddUnique(barcode)
txtWO.Clear()
txtWO.Focus()
End If
End Sub
The most simple decision is ONLY to make your textBox control txtWO NOT multiline
And that's enough! Your code will work correctly!
Ok so here's the relevant code:
Public Shared compSelect(9) As ComboBox
Public Shared compPercent(9) As TextBox
Private Sub MainForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Data.LoadComponents("C:/Users/Jon/Documents/Visual Studio 2013/Projects/QuickBlend/QuickBlend/QuickBlend/Resources/databaseText.txt")
MsgBox("finished loading")
MainForm.compSelect = {CompSelect1, CompSelect2, CompSelect3, CompSelect4, CompSelect5, CompSelect6, CompSelect7, CompSelect8, CompSelect9, CompSelect10}
MainForm.compPercent = {CompPercent1, CompPercent2, CompPercent3, CompPercent4, CompPercent5, CompPercent6, CompPercent7, CompPercent8, CompPercent9, CompPercent10}
For Each box As ComboBox In MainForm.compSelect
box.DataSource = Data.Components
box.DisplayMember = "Name"
For Each comp As String In Data.ComponentNames
box.Items.Add(comp)
Next
MsgBox("looped")
Next
MsgBox("finished loop")
End Sub
As you can see, I've placed various MsgBoxes to see exactly whats going on. It never displays the "looped" message box. Can anybody explain to me why it's completely skipping the for loop? Been working on this for a while and got fed up with it. Thanks in advance for the help! =)
MainForm.compSelect should be Me.compSelect since this is the instance(has been filled with comboboxes) and not just the fully qualified name of the object that has not been filled.
Your problem is that you are setting the datasource for the comboBox, and then trying to add items to it. .NET does not like this, and will just exit the Sub that tries to do this, without warning (unless you have exception handling added in). Your code should be...
Public Shared compSelect(9) As ComboBox
Public Shared compPercent(9) As TextBox
Private Sub MainForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Data.LoadComponents("C:/Users/Jon/Documents/Visual Studio 2013/Projects/QuickBlend/QuickBlend/QuickBlend/Resources/databaseText.txt")
MsgBox("finished loading")
MainForm.compSelect = {CompSelect1, CompSelect2, CompSelect3, CompSelect4, CompSelect5, CompSelect6, CompSelect7, CompSelect8, CompSelect9, CompSelect10}
MainForm.compPercent = {CompPercent1, CompPercent2, CompPercent3, CompPercent4, CompPercent5, CompPercent6, CompPercent7, CompPercent8, CompPercent9, CompPercent10}
For Each box As ComboBox In MainForm.compSelect
box.DataSource = Data.Components
box.DisplayMember = "Name"
'take this stuff out, it is not needed
'For Each comp As String In Data.ComponentNames
'box.Items.Add(comp)
'Next
MsgBox("looped")
Next
MsgBox("finished loop")
End Sub
When I load the form where some text has been given to text box. All the text in that textbox is highlighted. I want vb not to load it this way.
How to fix it.
Thanks
Furqna
You could set the tab index on your textbox to something else so that it's not the lowest index.
You could set the TextBox1.SelectionLength = 0 in the form.activated event.
I don't like this as much because if the user had the text hilited and minized the application then they will lose the hilite, but is fairly easy to do. I guess you could use a flag to make sure it only did it on the first activate.
You could set a timer event in the load to clear it immediately after the load event, but that seems like overkill. I have worked at places where they had a standard function that happened on every form 100 ms after load because of problems such as this.
You could try this(it looks like a workaround):
Private Sub TextBox1_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles TextBox1.GotFocus
TextBox1.SelectionStart = TextBox1.Text.Length
End Sub
It depends on the TabIndex of your TextBox, if it has the lowest TabIndex it gets focus and therefore it's Text is selected.
' VS.net 2013. Use the "Shown" event.
' GotFocus isn't soon enough.
Private Sub Form_Shown(sender As Object, e As EventArgs) Handles Me.Shown
TB.SelectionLength = 0
End Sub
Type 1 Method
Dim speech = CreateObject("sapi.spvoice")
speech.speak(TextBox1.Text)
Type 2 Method
Dim oVoice As New SpeechLib.SpVoice
Dim cpFileStream As New SpeechLib.SpFileStream
'Set the voice type male or female and etc
oVoice.Voice = oVoice.GetVoices.Item(0)
'Set the voice volume
oVoice.Volume = 100
'Set the text that will be read by computer
oVoice.Speak(TextBox1.Text, SpeechLib.SpeechVoiceSpeakFlags.SVSFDefault)
oVoice = Nothing
Type 3 Method
Imports System.Speech.Synthesis
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim spk As New SpeechSynthesizer
For Each voice As InstalledVoice In spk.GetInstalledVoices
ListBox1.Items.Add(voice.VoiceInfo.Name)
Next
ListBox1.SelectedIndex = 0
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim spk As New SpeechSynthesizer
spk.SelectVoice(ListBox1.SelectedItem.ToString)
spk.Speak(TextBox1.Text)
End Sub
End Class
This will also happen sometimes if The TextChanged or other similar Event is fired twice for the control.
When creating each form. Each object is indexed you can set the tab Index higher then the indexed object. Example: On the third form you put a text box in.
private void textBox1_TextChanged(object sender, EventArgs e)
This was the 12th object in the project, it would be indexed at 12. if you put the tab index higher then the indexed objects throughout the project. Tab index 1000 (problem solved.)
Have a great day.
Scooter