delphi 计算函数执行时间 TStopwatch

Posted 2020-12-25 yangxuming

先定义两个函数

    function sumX(x, y: Integer): Integer;
    function sumY(x, y: Integer): Integer; inline;

计算函数执行时间

procedure TForm5.Button5Click(Sender: TObject);
var
  sw: TStopwatch;
  i, j: Integer;
begin
  j := 0;
  sw := TStopwatch.StartNew;
  for i := 0 to 100000000 do
  begin
    j := sumX(i, j); //普通函数 
  end;
  sw.Stop;
  ShowMessage(‘first do expand time =‘ + IntToStr(sw.ElapsedMilliseconds) + ‘ ‘); //602

  j := 0;
  sw := TStopwatch.StartNew;
  for i := 0 to 100000000 do
  begin
    j := sumY(i, j);   //inline函数
  end;
  sw.Stop;
  ShowMessage(‘second do expand time =‘ + IntToStr(sw.ElapsedMilliseconds) + ‘ ‘); //595

end;