I am using a TMemo to hold received characters from a serial port for viewing. As they arrive I am doing:
Memo1.Text := Memo1.Text + sReceivedChars;
This works fine but I presume it is rather inefficient, having to get the existing text before concate开发者_StackOverflownating my few characters and then writing it back. I would really like a 'SendChars()' function or something similar. Is there a better way of simply adding a few characters on the end of the existing text?
I don't know if you think it's worthwhile, but you can do something like this:
procedure TForm1.Button1Click(Sender: TObject);
var
index: Integer;
NewText: string;
begin
NewText := 'Append This';
index := GetWindowTextLength (Memo1.Handle);
SendMessage(Memo1.Handle, EM_SETSEL, index, index);
SendMessage (Memo1.Handle, EM_REPLACESEL, 0, Integer(@NewText[1]));
end;
If your text is in more than one line (strings of a the TStrings
collection that is the actual type of the Lines
property of the TMemo), then you could do this:
Memo1.Lines[Memo1.Lines.Count - 1] := Memo1.Lines[Memo1.Lines.Count - 1] + sReceivedChars;
So you add some chars to the last line (the last string in the string collection) of the memo, without taking the whole text into a single string.
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