用GetTickCount()计算一段代码执行耗费的时间的小例子

var 
    aNow,aThen,aTime:Longint;
begin
    aThen := GetTickCount();
    Sleep(1000);//代码段
    aNow := GetTickCount();
    aTime := aNow-aThen;
    ShowMessage(IntToStr(a));
end;