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AutoIndent (Auto Indent) in RichTextBox Control

Hi Experts,
I am making a small customized Editor in vb6 and am using a RichTextBox. Every thing is fine so far... but now i am stuck at a point where when the user presses enter key the cursor should move to then next line and automatically indent to the number of tabs pressed in the previous line... Just like VB's own IDE and Word etc.

i have looked at SelTabCount, SelTabs, SelIndent properties but am totally lost and have no iedea where to go from here onwards....

a quick response will be much appriciated.

thanx,
msa.

mcrider

Here's a quick example you can try... It may not be perfect, but it will give you a general idea...

1) Start a new project.

2) Add a richtextbox control to the form.

3) Add the following code to the declarations section of the form:

'-------------------------------------------------------------------------------
Dim arrTabStop() As Boolean
Dim TabCounter As Long
Dim InhibitTabCount As Boolean
Dim EnterProcessing As Boolean
Private Declare Function LockWindowUpdate Lib "user32" _
(ByVal hwndLock As Long) As Long
Private Sub Form_Load()
RichTextBox1.Text = ""
End Sub
Private Sub RichTextBox1_GotFocus()
'Store the TabStop property for each control on the
'form and then set the TabStop property of each
'control to False
ReDim arrTabStop(0 To Controls.Count - 1) As Boolean
For i = 0 To Controls.Count - 1
arrTabStop(i) = Controls(i).TabStop
Controls(i).TabStop = False
Next
End Sub
Private Sub RichTextBox1_KeyPress(KeyAscii As Integer)
Dim iVal As Long

Select Case KeyAscii
Case 8 'BACKSPACE
With RichTextBox1
If .GetLineFromChar(.SelStart) = 0 Then
If .SelStart <= TabCounter + 1 Then
TabCounter = TabCounter - 1
End If
Else
If InhibitTabCount = False Then
TabCounter = TabCounter - 1
Else
If InStr(.SelStart - 2, .Text, vbCrLf) > 0 Then
TabCounter = TabCounter - 1
End If
End If
End If
If TabCounter < 0 Then TabCounter = 0
End With

Case 9 'TAB
If InhibitTabCount = False Then
TabCounter = TabCounter + 1
End If

Case 13 'ENTER
If EnterProcessing = False Then
EnterProcessing = True
InhibitTabCount = True
SendKeys "~", True
LockWindowUpdate RichTextBox1.hWnd
For iVal = 1 To TabCounter
SendKeys "{TAB}", True
Next iVal
LockWindowUpdate 0&
InhibitTabCount = False
EnterProcessing = False
KeyAscii = 0
End If

Case Else 'ALL OTHER KEYS
InhibitTabCount = True
End Select
End Sub
Private Sub RichTextBox1_LostFocus()
'Restore the Tabstop property for each control on the form
For i = 0 To Controls.Count - 1
Controls(i).TabStop = arrTabStop(i)
Next
End Sub
'-------------------------------------------------------------------------------

4) Run the program and then type:

{TAB}{TAB}This is a test

When you hit the ENTER key, the next line will start indented 2 tabs...

Play around with it...

Cheers!®©

msali

ASKER

Thanx for the code it works for me so far... and will modify it to my custom need....

would like to give u points for it .... so pls lock it so that i can give u points.

later,
msa.

msali

ASKER

Thanx for the code it works for me so far... and will modify it to my custom need....

would like to give u points for it .... so pls lock it so that i can give u points.

later,
msa.

ASKER CERTIFIED SOLUTION

mcrider

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msali

ASKER

just a clearification....what is the purpose of LockWindowUpdate API

thanx

mcrider

LockWindowUpdate freezes the update of the hWnd passed to it... In this case, it freezes the RTbox so that the tabs sent to the RTbox are not seen "one at a time"... All of the tabs are sent with the control locked and then it's unlocked to refresh the control.

Thanks for the points! Glad I could help!

Cheers!®©

mcrider

By the way to unlock the last LockWindowUpdate, you do:

LockWindowUpdate 0&

Cheers!®©