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TThread.Terminate

Signals the thread to terminate by setting the Terminated property to True.

procedure Terminate;

Description

Terminate sets the thread’s Terminated property to True, signaling that the thread should be terminated as soon as possible. Unlike the Windows API TerminateThread, which forces the thread to terminate immediately, the Terminate method merely requests that the thread terminate. This allows the thread to perform any cleanup before it shuts down.

For Terminate to work, the thread's Execute method and any methods that Execute calls should check Terminated periodically and exit when it's True.

Код:

var
  MyClientThread: TMyClientThread;

procedure TForm1.Button1Click(Sender: TObject);
begin
  MyClientThread.Terminate;
end;

procedure TMyClientThread.Execute;
begin
    while  not Terminated do
    begin
...
    end;
end;