TMEMO How to get line of the tmemo underneath mouse cursor?

[Josh]

Hi

How can I get the line of the text undeneath the mouse cursor of a tmemo, the caretpos is no use as you have to click the line? Hopefully there is a cross platfprm way.

Ideally if there is a way to convert the mouse.cursor ordinates to the tmemo to get the line underneath..

Thnks in advance.

[rvk]

For Windows ok?

Something like this:

Code: Pascal  [Select][+][-]

1. uses Windows;
2.  
3. procedure TForm1.Memo1MouseMove(Sender: TObject; Shift: TShiftState; X, Y: integer);
4. var
5.   Pt: integer;
6.   Idx: DWord;
7.   CharIdx, LineIdx, Col: word;
8. begin
9.   Pt := (X and $FFFF) or ((Y and $FFFF) shl 16);
10.   Idx := SendMessage(Memo1.Handle, EM_CHARFROMPOS, 0, Pt); // linesindex and character index in memo
11.   CharIdx := Idx and $FFFF;
12.   LineIdx := (Idx shr 16) and $FFFF;
13.   Col := Idx - SendMessage(Memo1.Handle, EM_LINEINDEX, LineIdx, 0); // get col within line
14.   Inc(LineIdx); // was 0-based
15.   Inc(Col); // was 0-based
16.   Label1.Caption := Format('X %d  Y %d', [X, Y]);
17.   Label2.Caption := Format('Line: %d Pos: %d', [LineIdx, Col]);
18. end;

Notes:
- Pos doesn't go beyond the line.
- except for the last character. If mouse is beyond the line the Pos is Linelength + 1.