Delphi 7: How to implement multi-threading?

Question

I have a TButton in the main TForm. When user click the button, it will execute the below process:

begin
  Process_done := FALSE;

  Process_Result.Clear;

  cmd         


        

Answer 1

You should create a class inherited from TThread and put that code in there. I don't remember exactly, but I think you'll find TThread template in File->New dialog box. When code execution is finished, you just notify your gui. Here's an article how to synchronize UI with external thread http://delphi.about.com/od/kbthread/a/thread-gui.htm

Answer 2

Try something like this:

type
  TRunProcessThread = class(TThread)
  protected
    cmdProcess: Whatever;
    procedure Execute; override;
  public
    constructor Create(const ACmdLine: String);
    destructor Destroy; override;
  end;

constructor TRunProcessThread.Create(const ACmdLine: String);
begin
  inherited Create(True);
  FreeOnTerminate := True;
  cmdProcess := Whatever.Create;
  cmdProcess.CommandLine := ACmdLine;
end;

destructor TRunProcessThread.Destroy;
begin
  cmdProcess.Free;
  inherited;
end;

procedure TRunProcessThread.Execute;
begin
  cmdProcess.Run;
  ...
end;

.

procedure TForm1.Button1Click(Sender: TObject);
var
  Thread: TRunProcessThread;
begin
  Thread := TRunProcessThread.Create(AnsiQuotedStr(AppPath + 'getdata.exe', #34));
  Thread.OnTerminate := ProcessDone;
  Thread.Resume;
end;

procedure TForm1.ProcessDone(Sender: TObject);
begin
  // access TRunProcessThread(Sender) to get result information as needed ...
end;