Delphi

Question:
I want to trace progress inside DLL, what kind of methode suitable for that?

Answer:
Usually, I use sendmessage, because it easy, light, simple and wont interupt your memory management. Here the example:


const
MY_MESSAGE = WM_USER + 4242;

type
TForm1 = class(TForm)
Button1: TButton;

procedure Button1Click(Sender: TObject);
// Handler that receive the Message

procedure MessageReceiver(var msg: TMessage); message MY_MESSAGE;
end;
var
Form1: TForm1;
implementation
{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
var
txt: string;
begin
txt := 'Hello World';
SendMessage(Form1.Handle, MY_MESSAGE, 0, DWORD(PChar(txt)));
end;

procedure TForm1.MessageReceiver(var msg: TMessage);
var
txt: PChar;
begin
txt := PChar(msg.lParam);
msg.Result := 1;
ShowMessage(txt);
end;
end.