Text Box Scroll

[SIMIN]

Hello,

It seems to be strange, but in a loop, when I add some text to the text box like this:

 

For X = 1 to 100

TextBox1.Text = TextBox1.Text + "Text" + vbNewLine

Next

 

However, the scroll bar will stay at top and I can only see the first few lines of text box, even if I move the scroll bar to down, it will jump back to top as soon as text inside the text box changes.

I want to change this scenario, so scroll bar will stay at down so I can see the last lines of text inside text box.

I don't know how can this be done, but I know it's possible because I've seen some applications like this! :confused:

Thank you.

[MrPaul]

SelectionStart

 

A quick-and-dirty implementation might looks like this:

 

For X = 1 to 100
   TextBox1.Text += "Text" + ControlChars.NewLine
   TextBox1.SelectionStart = TextBox1.Text.Length
Next

 

Good luck! :cool:

[digioz]

Paul's code didn't work for me. But this does:

 

   Private Const WM_VSCROLL As Int32 = &H115
   Private Const SB_BOTTOM As Int32 = 7

   Private Declare Auto Function SendMessage Lib "user32.dll" ( _
       ByVal hwnd As IntPtr, _
       ByVal wMsg As Int32, _
       ByVal wParam As Int32, _
       ByVal lParam As Int32 _
   ) As Int32

   Private Sub AddLine(ByVal loDestination As RichTextBox, ByVal lsText As String)
       With loDestination
           .AppendText(lsText & ControlChars.NewLine)
           SendMessage(loDestination.Handle, WM_VSCROLL, SB_BOTTOM, 0)
       End With
   End Sub

   Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click
       Dim i As Integer = 0

       For i = 0 To 300
           AddLine(txtProgress, "Line " & i)
       Next
   End Sub

 

Pete

[snarfblam]

Try this.

For X = 1 to 100

    TextBox1.Text += "Text" + ControlChars.NewLine

    TextBox1.SelectionStart = TextBox1.Text.Length

  [i]  TextBox1.ScrollToCaret()[/i]

Next

[/Code]

[digioz]

Try this.

For X = 1 to 100

    TextBox1.Text += "Text" + ControlChars.NewLine

    TextBox1.SelectionStart = TextBox1.Text.Length

  [i]  TextBox1.ScrollToCaret()[/i]

Next

[/Code]

 

Nope, doesn't work. The only one I could get to work was the code I posted. Your code does make sense. But it doesn't work in VS 2005 for me. :(

 

 

Pete

[Erel]

Works fine here:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
       Dim i As Integer
       For i = 1 To 100
           TextBox1.Text += "Text" + i.ToString + ControlChars.NewLine
           TextBox1.SelectionStart = TextBox1.Text.Length
           TextBox1.ScrollToCaret()
       Next
End Sub

[digioz]

Works fine here:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
       Dim i As Integer
       For i = 1 To 100
           TextBox1.Text += "Text" + i.ToString + ControlChars.NewLine
           TextBox1.SelectionStart = TextBox1.Text.Length
           TextBox1.ScrollToCaret()
       Next
End Sub

 

Hmm... I wonder why it doesn't work for me. I have a regular textbox, with "Multiline=True", and "Scrollbar=Vertical". Is that what you have? Am I missing something? I am trying it in VS 2005. Is that what you are using?

 

Thanks,

Pete

[Erel]

Hmm... I wonder why it doesn't work for me. I have a regular textbox, with "Multiline=True", and "Scrollbar=Vertical". Is that what you have? Am I missing something? I am trying it in VS 2005. Is that what you are using?

 

Thanks,

Pete

 

Yes. :confused:

When I run this code I see the numbers climb up to 100 and the scrollbar stays at the bottom.