怎么计算两个时间的差值？

[liyong00512]

是日期类型的，得到的结果是天数。

[午秋]

i:=trunc(dt2)-trunc(dt1);

[sandzou]

var

[sandzou]

var i:integer;

i:=dt2-dt1;

..............ok...........:)

[xfgncit98]

用DaySpan这个函数吧。
function DaySpan(const ANow, AThen: TDateTime): Double;

Returns the number of days (including fractional days) between two specified TDateTime values.Call DaySpan to obtain the difference, in days, between two TDateTime values. Unlike the DaysBetween function, which only counts whole days, DaySpan reports incomplete days as a fraction of an entire day.

[周江涛]

看这个单元，什么函数都有DateUtils

[senhor]

楼上的：
Uses
DateUtils

[tglong]

trunc(dt2)-trunc(dt1)

[dxwin]

delphi帮助里：
Unit
DateUtils

Category
datetime routines

Delphi syntax:
function DaySpan(const ANow, AThen: TDateTime): Double;

Description
Call DaySpan to obtain the difference, in days, between two TDateTime values. Unlike the DaysBetween function, which only counts whole days, DaySpan reports incomplete days as a fraction of an entire day.

[jan2002]

DaysBetween Function

Returns the number of whole days between two specified TDateTime values.

Unit

DateUtils

Category

date/time routines

function DaysBetween(const ANow, AThen: TDateTime): Integer;

Description

Call DaysBetween to obtain the difference, in days, between two TDateTime values.

DaysBetween counts only whole days that have elapsed. Thus, DaysBetween reports the difference between Dec 31, 1999 11:59 PM and Jan 1, 2000 11:58 PM as 0 because the difference is one minute short of an entire day.

[pingwing]

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