How to get the physical caret position in a TMemo, TEdit or TRichEdit #103
Question
How to get the caret position of a Memo or RichEdit control? I don't
mean any character position expressed in row and column, I mean it in
pixels!
You get the caret position in pixels (client relative) from an edit, memo or richedit control by sending it a EM_POSFROMCHAR message. The message parameters are different for a TRichEdit and TMemo / TEdit.
TRichEdit:
var pt: TPoint; begin with richedit1 do begin Perform(messages.EM_POSFROMCHAR, WPARAM(@pt), selstart); label1.caption := Format('(%d, %d)', [pt.x, pt.y]); end; end;
TMemo and TEdit
var r: LongInt; begin with memo1 do begin r := Perform(messages.EM_POSFROMCHAR, selstart, 0); if r >= 0 then begin label1.caption := IntToStr(HiWord(r)); label2.caption := IntToStr(LoWord(r)); end; end; end;
The win32.hlp
entries for this message are really messed up, on
older versions they only showed the memo variant, on newer (e.g. the one
that comes with D5) they show only the richedit variant.
Original resource: | The Delphi Pool |
---|---|
Author: | Peter Below |
Added: | 2009/09/14 |
Last updated: | 2009/09/14 |