时间相减简单问题

Question

T1='2005-7-19 6:00:00'
T2='8:00:00'哪个函数可以得到下面的结果.
T1-T2=
'2005-7-18 22:00:00'thx

Answer 1

如何知道你的T2是哪天呢？
UP一下....

Answer 2

T2不是天数，是小时.
指8小时。
用now()-8小时.

Answer 3

T1='2005-7-19 6:00:00'
T2='8:00:00'
-------------------------------------------
function func(const T1,T2:String):String;
var
  d1:TDateTime;
  d2:TDateTime;
begin
  d1:=StrToDateTime(T1);
  d2:=StrToTime(T2);
  Result:=DateTimeToStr(d1+d2);
end;

Answer 4

procedure TForm1.Button1Click(Sender: TObject);
var
  iDate:TDateTime;
  iTime:TDateTime;
begin
  iDate:=strtodatetime('2005-7-19 6:00:00');
  iTime:=strtodatetime('8:00:00');
  showmessage(datetimetostr(iDate));
  iDate:=iDate-iTime;
  showmessage(datetimetostr(iDate));
end;//时间就是double型，直接加减就OK

Answer 5

哈哈，不好意思，减写成加了^_^
======================================
function func(const T1,T2:String):String;
var
  d1:TDateTime;
  d2:TDateTime;
begin
  d1:=StrToDateTime(T1);
  d2:=StrToTime(T2);
  Result:=DateTimeToStr(d1-d2);
end;procedure TForm1.FormCreate(Sender: TObject);
begin
   ShowMessage(func('2005-7-19 6:00:00','8:00:00'));
end;

Answer 6

begin
   ShortDateFormat:='yyyy-m-d';
   DateSeparator:='-';
   ShowMessage(DateTimeToStr(StrToDateTime('2005-7-19 6:00:00')-StrToTime('8:00:00')));
end;