[RESOLVED] EM_GETLINE LaVolpe-KoolSid conversation

[r-max]

Hello,
Recently I have use the above code which was displayed by Koolsid I belive.
I have used it before with no single problem up to 1200 lines .
But that was then, now I have RTB up to 3000 lines.
Reads fine until hits 2020 line and from that moment returns to the 1st line
and continuously duplicate it to the end of calculated number of all lines.
In this code, is there a buffer limitation ?
Is there something I don’t know and should know?

Option Explicit 

Private Declare Function SendMessage Lib "user32" _
Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, _
ByVal wParam As Long, lParam As Any) As Long
    
Private Const EM_GETLINECOUNT = &HBA
Private Const EM_GETSEL = &HB0
Private Const EM_LINEINDEX = &HBB
Private Const EM_LINELENGTH = &HC1
Private Const EM_LINEFROMCHAR = &HC9
Private Const EM_GETLINE = &HC4
  Dim RTBLineCount As Long, Charindex As Long
  Dim FirstChar As Long, RowLength As Long, CursorPos As Long, nLine As Long
  Dim Buffer() As Byte, LineText A

************************************

Sub part

RTBLineCount = SendMessage(RichTextBox1.hwnd, EM_GETLINECOUNT, 0, 0)

    
    
    For i = 0 To RTBLineCount - 1
        
        ccnt = ccnt + 1
        Charindex = SendMessage(RichTextBox1.hwnd, EM_LINEINDEX, ByVal i, ByVal CLng(0))
    
        RichTextBox1.SelStart = Charindex
    
        CursorPos = SendMessage(RichTextBox1.hwnd, EM_GETSEL, 0, ByVal 0&) \ 65536
        nLine = SendMessage(RichTextBox1.hwnd, EM_LINEFROMCHAR, CursorPos, ByVal 0&)
        FirstChar = SendMessage(RichTextBox1.hwnd, EM_LINEINDEX, nLine, ByVal 0&)
        RowLength = SendMessage(RichTextBox1.hwnd, EM_LINELENGTH, FirstChar, ByVal 0&)
        ReDim Buffer(RowLength + 1)
        Buffer(0) = RowLength + 1

        SendMessage RichTextBox1.hwnd, EM_GETLINE, nLine, Buffer(0)
        LineText = Left$(StrConv(Buffer, vbUnicode), RowLength-6) ' single line, less 6 right cut.
        
         
        ' ***************
       'LineText = Replace(LineText, "  ", " ") good but not to be use here
      
	TX = Trim(LineText)
             Do While InStr(TX, "  ")
        TX = Replace$(TX, "  ", " ") 
             Loop
              
       RichTextBox3.Text = RichTextBox3.Text & TX & vbNewLine
       
       Next i

[MartinLiss]

Did you mean to add this as a post to an existing thread? If so provide me with the URL and I'll move it there.

[LaVolpe]

Maybe... The problem is with the EM_GETSEL call.
If the character position at that point is > 65535 then the return value is -1 and -1\ 65536 is zero, back to the first character. There is a workaround

But first, I'm confused by your code:
1. You are looping thru RTF#1, ok
2. You are setting CharIndex to 1st character of each line, ok
3. You are setting the .SelStart, why? Just for visual effect?
4. You are then trying to set CursorPos which is failing but CursorPos should equal CharIndex when it doesn't fail
5. You are trying to set nLine, but isn't nLine = i ?
6. You are setting FirstChar, but FirstChar should = CharIndex
7. RowLength at this point could be retrieved by using CharIndex

So from what I see is CharIndex = FirstChar = CursorPos (if -1 not returned). Also i = nLine

Aside from the confusion, if you need the workaround to get a valid character index from a rtf that has more than 65K characters, I can provide that.

[MartinLiss]

Your CursorPos calculation is perhaps the cause but I don't know for sure. Are you familiar with the Debug module? If not then maybe you could benefit from my VB6 Debug Tutorial.

[r-max]

Yes, I would like to leave it as is as a new post.
I have found a conversation between those two guys in a similar topic
and I was hoping that one of them, or anyone in this matter would explain it to me.
Many thanks,

[r-max]

LaVolpe, Thanks for replay.
Any idea from you would be greatly appreciated to correct all this
and have better understanding the issue here.
Much appreciated.

[MartinLiss]

If you want to try to debug you could set a breakpoint to pause the code when i gets to 2020 and then step through the code line by line examining the variables to see what's happening. That's a pretty sure way to find the problem and a solution.

[LaVolpe]

A quick fix, using your code.... but tweaking it

For nLine = 0 To RTBLineCount - 1
        
        ccnt = ccnt + 1
        Charindex = SendMessage(RichTextBox1.hwnd, EM_LINEINDEX, nLine, ByVal 0&)
    
        RichTextBox1.SelStart = Charindex
        RowLength = SendMessage(RichTextBox1.hwnd, EM_LINELENGTH, CharIndex, ByVal 0&)
        ReDim Buffer(RowLength + 1)
        Buffer(0) = RowLength + 1

        SendMessage RichTextBox1.hwnd, EM_GETLINE, nLine, Buffer(0)
        LineText = Left$(StrConv(Buffer, vbUnicode), RowLength-6) ' single line, less 6 right cut.
        
...

Copy your current code before replacing this, just in case the tweaks affect something else you didn't show us.
Note that the variables i, FirstChar, CursorPos are no longer used in the above tweaks.

[r-max]

Hello LaVolpe,

A “ quick fix “ does work OK,
I had to change this line to:

For nLine = 0 To RTBLineCount - 2

I misted the Line counter somewhere on the way, but that is nothing compare to what it was.
I also must stick to this routine from now on since I use this procedure a lot.
Actually, if you would have in your sleeve this procedure written your way
I would appreciate if you could share this idea with me.
Many Thanks, problem solved, excellent respond!