function BlockInput (fBlockInput : boolean) : DWord; stdcall; external 'user32.DLL'; <br>procedure TForm1.Button1Click(Sender: TObject); <br>begin <br> BlockInput(true); <br>end; <br>procedure TForm1.Button2Click(Sender: TObject); <br>begin <br> BlockInput(false); <br>end; <br><br>