Author: Misha Moellner

How to set margins in a TMemo

Answer:

EM_SETRECT message is sent to Memo to fix the size of the canvas of the component. 
1   
2   procedure TForm1.Button1Click(Sender: TObject);
3   var
4     R: TRect;
5     LeftMargin: integer;
6     RightMargin: integer;
7   begin
8     LeftMargin := 20;
9     RightMargin := 10;
10  
11    R := Memo1.ClientRect;
12    R.Left := R.Left + LeftMargin;
13    R.Top := R.Top + 2;
14    R.Bottom := R.Bottom - 2;
15    R.Right := R.Right - RightMargin;
16    SendMessage(Memo1.Handle, EM_SETRECT, 0, Longint(@R));
17  end;