Delphi 常用日期与时间函数课件

1、Delphi 常用日期与时间函数1 获取特定的日期与时间本小节将为您介绍Delphi 所提供的获取特定日期与时间的函数.这些函数稍后将有详细的范例说明.笔者这里将以列表的方式先说明每一个函数所代表的意义,如图示:函数名称单元文件所代表的意义NowSysUtils此函数可返回现在的日期与时间,其返回值为TDateTime类型DateSysUtils此函数可返回现在的日期,其返回值为TDateTime类型TimeSysUtils此函数可返回现在的时间,其返回值为TDateTime类型TodayDateUtils此函数可返回今天的日期,其返回值为TDateTime类型,此函数的结果与Date函数相同

2、.TomorrowDateUtils此函数可返回昨天的日期,其返回值为TDateTime类型YesterdayDateUtils此函数可返回明天的日期,其返回值为TDateTime类型CurrentyearSysUtils此函数可返回现在所属的年度,其返回值为4的整数.例如:2001HoursperdaySysUtils此常数定义每天的小时数.HoursPerDay =24;MinsperdaySysUtils此常数定义每天的分钟数.MinsPerDay = MinsPerDay*60SecsperdaySysUtils此常数定义每天的秒数.SecPerDay = MinsPerDay *60

3、msecsperdaySysUtils此常数定义每天的毫秒数.MSecsPerDay =SecsperDay*1000Now (返回当前的日期时间)引用单元:SysUtils函数声明:Function Now : TDateTime;范例D-1Procedure TForm1.Button1Click(Sender: TObject);VarMyDateTime : TDateTime;beginMyDateTime :=Now; Showmessage(DateTimeToStr(MyDateTime);end;Date(返回当前的日期)引用单元:SysUtils函数声明:Function

4、Day :TDateTime;范例D-2Procedure TForm1.Button1Click(Sender: TObject);VarMyDateTime : TDateTime;beginMyDateTime :=Date; Showmessage(DateTimeToStr(MyDateTime);end;Time(返回当前的时间)引用单元:SysUtils函数声明:Function Time:TDateTime;范例D-3Procedure TForm1.Button1Click(Sender: TObject);VarMyDateTime : TDateTime;beginMyD

5、ateTime :=Time; Showmessage(DateTimeToStr(MyDateTime);end;Today(返回今天的日期)引用单元:DateUtils函数声明:Function Today :TDateTime;范例D-4Procedure TForm1.Button1Click(Sender: TObject);VarMyDateTime : TDateTime;Begin/uses DateUtilsMyDateTime :=Today; Showmessage(DateTimeToStr(MyDateTime);end;Tomorrow(返回明天的日期)引用单元:D

6、ateUtils函数声明:Function Tomorrow:TDateTime;范例D-5Procedure TForm1.Button1Click(Sender: TObject);VarMyDateTime : TDateTime;Begin/uses DateUtilsMyDateTime :=Tomorrow; /MyDateTime : Now +1; /两者相同Showmessage(DateTimeToStr(MyDateTime); /不包含时间部分end;Yesterday(返回昨天的日期)引用单元:DateUtils函数声明:Function Yesterday :TDa

7、teTime;范例D-6Procedure TForm1.Button1Click(Sender: TObject);VarMyDateTime : TDateTime;Begin/uses DateUtilsMyDateTime :=Yesterday; /MyDateTime : Now -1; /两者相同Showmessage(DateTimeToStr(MyDateTime); /不包含时间部分end;CurrentYear(返回现在所属的年度)引用单元:SysUtils函数声明:Function CurrentYear :Word;范例D-7Procedure TForm1.Butt

8、on1Click(Sender: TObject);VarThisYear: Word;Beginthis year := CurrentYear;Showmessage(IntToStr(ThisYear); / 4位整数end;HoursPerDay,MinsPerDay,SecsPerDay及MsecsPerDay等日期与时间常数.引用单元:SysUtils函数声明:Function CurrentYear:Word;范例D-8Procedure TForm1.Button1Click(Sender: TObject);BeginShowmessage('每天的小时数='

9、 + IntToStr(HoursperDay); /24 Showmessage('每天的分钟数=' + IntToStr(MinsperDay); / 1440Showmessage('每天的秒数=' + IntToStr(SecsperDay); /24 Showmessage('每天的毫秒数=' + IntToStr(MSecsperDay); /24 end;D.2 日期处理函数:函数名称单元文件所代表的意义YearOfDateUtils此函数可获取TDateTime格式中的年度,其返回值为Word类型.YearsBeTweenDate

10、Utils此函数可返回两个指定日期间的年份,一年以365.25天为计算单位.其返回值不包含小数部分YearSpanDateUtils此函数可返回两个指定日期间的年份,一年以365.25天为计算单位.其返回值包含小数部分StartOfAYearDateUtils此函数可返回特定年份的第一天EndOfAYearDateUtils此函数可返回特定年份的最后一天StrtOfTheYearDateUtils此函数可返回特定日期的该年第一天EndOfTheYearDateUtils此函数可返回特定日期的该年最后一天IncYearDateUtils此函数可将指定的TDateTime变量加上指定的年度,其默认

11、值为1年MonthOfDateUtils此函数可获取TDateTime格式中的月份,其返回值为Word类型MonthOfTheYearDateUtils此函数可获取TDateTime格式中的月份,其返回值为Word类型MonthBetweenDateUtils次函数可返回两个指定日期间的月份数,一个月以30.4375天为计算单位.其返回值不包含小数部分MonthSpanDateUtils次函数可返回两个指定日期间的月份数,一个月以30.4375天为计算单位.其返回值包含小数部分StartOfAMonthDateUtils此函数可返回特定年月的第一天EndOfAMonthDateUtils此函数

12、可返回特定年月的最后一天StartOfTheMonthDateUtils此函数可返回指定日期的该年的第一天EndOfTheMonthDateUtils此函数可返回指定日期的该年的最后一天IncMonthDateUtils此函数可将指定的TDateTime变量加上指定的月份,其默认值为加上1个月IncAMonthDateUtils此函数可将指定的年月日加上指定的月份,其默认值为加上1个月DaysInAYearDateUtils此函数可返回指定年份的总天数DaysInYearDateUtils此函数可返回指定TDateTime变量中该年分的总天数DaysInAMonthDateUtils此函数可返

13、回指定月份的总天数DaysInMonthDateUtils此函数可返回指定TDateTime变量中该月份的总天数DaysOfDateUtils此函数可获取TDateTime格式中的日期,其返回值为Word类型DaysBetweenDateUtils此函数可获取格式中的日期,其返回值不包含小数部分DaySpanDateUtils此函数可返回两个指定日期间的天数,其返回值包含小数部分DayOfTheYearDateUtils此函数可返回指定TDateTime变量为该年的第几天.例如2月1日则返回32DayOfTheMonthDateUtils此函数可返回指定TDateTime变量为该月的第几天,其

14、返回值介于1到31DayOfTheWeekDateUtils此函数可返回指定TDateTime变量为该周的第几天,其返回值介于1到7.星期一为第一天.DayOfWeekDateUtils此函数可返回指定TDateTime变量为该周的第几天,其返回值介于1到7.星期日为第一天.StartOfADayDateUtils此函数可返回指定日期一天的开始时间,其返回值为TDateTime类型.其时间默认为12:00:000 AMEndOfADayDateUtils此函数可返回指定日期一天的结束时间,其返回值为TDateTime类型.其时间默认为11:59:999 PMStartOfTheDayDateU

15、tils此函数可返回指定TDateTime变量的一天开始时间,其返回值为TDateTime类型.其时间默认为:12:00:000 AMEndOfTheDayDateUtils此函数可返回指定TDateTime变量的一天结束时间,其返回值为TDateTime类型.其时间默认为11:59:999PMIncDayDateUtils此函数可为指定日期加上特定的天数,其返回值为TDateTime类型,其默认天数为1天WeeksInAYearDateUtils此函数可返回指定年度的周数,其返回值不是52就是53WeeksInYearDateUtils此函数可返回指定TDateTime变量的周数,其返回值不

16、是52就是53WeekOfDateUtils次函数可返回指定日期为该年的第几周,其返回值为153WeekOfTheYearDateUtils次函数可返回指定日期为该年的第几周,其返回值为153WeekOfTheMonthDateUtils次函数可返回指定日期为该月的第几周,其返回值为16WeeksBetweenDateUtils此函数可返回两个指定日期间的周数,其返回值不包含小数部分WeekSpanDateUtils此函数可返回两个指定日期间的周数,其返回值包含小数部分StartOfAweekDateUtils此函数可返回指定日期一周的开始时间,其返回值为TDateTime类型.其时间默认为1

17、2:00:000 PMEndOfAWeekDateUtils此函数可返回指定日期一周的结束时间,其返回值为TDateTime类型.其时间默认为11:59:999 PMStartOfTheWeekDateUtils此函数可返回指定TDateTime变量的一周开始时间,其返回值为TDateTime类型.其其时间默认为12:00:000 AMEndOfTheWeekDateUtils此函数可返回指定TDateTime变量的一周结束时间,其返回值为TDateTime类型.其时间默认为11:59:999 AMIncWeekDateUtils此函数可将指定日期加上指定周数,其返回值为TDateTime类型

18、YearOf(返回指定日期的年度)引用单元:DateUtils函数声明:Function YearOf ( const AValue : TDateTime) :Word;范例D-9Procedure TForm1.Button1Click(Sender: TObject);Begin/三者都相同Showmessage('年度=' + IntToStr(YearOf(Now); Showmessage('年度=' + IntToStr(YearOf(Date); Showmessage('年度=' + IntToStr(YearOf(Today)

19、; end;YearsBetween(返回两个指定日期间的年份)引用单元:DateUtils函数声明:Function YearsBetween ( const ANow, AThen : TDateTime) :Integer;范例D-10Procedure TForm1.Button1Click(Sender: TObject);Begin/不包含小数,一年以365.25天为计算单位Showmessage('几年=' + IntToStr(YearsBetween(Now,Now+560); /1end;YearSpan(返回两个指定日期间的年份)引用单元:DateUtil

20、s函数声明:Function YearsSpan( const ANow , AThen : TDateTime) :Double;范例D-11Procedure TForm1.Button1Click(Sender: TObject);Begin/包含小数,一年以365.25天为计算单位Showmessage('几年=' + FloatToStr(YearSpan(Now,Now+560);/1.53.end;StartOfAYear(返回特定年份的第一天)引用单元:DateUtils函数声明:Function StartOfAYear ( const AYear) : TD

21、ateTime;范例D-12Procedure TForm1.Button1Click(Sender: TObject);BeginShowmessage(DateTimeToStr(StartOfAYear(2001);/2001/1/1 早上12:00:00end;EndOfAYear(返回特定年份的最后一天)引用单元:DateUtils函数声明:Function EndOfAYear ( const AYear) : TDateTime;范例D-13Procedure TForm1.Button1Click(Sender: TObject);BeginShowmessage(DateTi

22、meToStr(EndOfAYear(2001);/2001/12/31 下午11:59:59end;StartOfTheYear(返回指定日期的该年的第一天)引用单元:DateUtils函数声明:Function StartOfTheYear ( const AValue : TDateTime) :TDateTime;范例D-14Procedure TForm1.Button1Click(Sender: TObject);BeginShowmessage(DateTimeToStr(StarOfTheYear(Now);/指定的年度/1/1早上12:00:00end;EndOfTheYea

23、r(返回指定日期的该年的最后一天)引用单元:DateUtils函数声明:Function EndOfTheYear ( const AValue : TDateTime) :TDateTime;范例D-15Procedure TForm1.Button1Click(Sender: TObject);BeginShowmessage(DateTimeToStr(StarOfTheYear(Now);/指定年度/12/31下午11:59:59end;IncYear(将指定的TDateTime变量加上指定的年)引用单元:DateUtils函数声明:Function IncYear ( const A

24、Value : TDateTimel; const ANumberOfYears : Integer =1) :TDateTime;范例D-16 Procedure TForm1.Button1Click(Sender: TObject);varmyDateTime : TDateTime;BeginmyDateTime : = IncYear(Now,3); /往后加3年Showmessage(DateTimeToStr(myDateTime);End;MonthOf(获取TDateTime格式中的月份)引用单元:DateUtils函数声明:Function MonthOf ( const

25、AValue : TDateTime) :Word;范例D-17 Procedure TForm1.Button1Click(Sender: TObject);varmyDateTime : TDateTime;m : Integer;BeginmyDateTime : = Now; /两个函数获取相同的结果m := MonthofTheYear(myDateTime);Showmessage(IntToStr(m);end;MonthOfTheYear(获取TDateTime格式中的月份)引用单元:DateUtils函数声明:Function MonthOfTheYear ( const A

26、Value : TDateTime) :Word;范例D-18 Procedure TForm1.Button1Click(Sender: TObject);vari :Integer;f :Double;Begini := MonthsBetween(Now,Now+89);/差89天Showmessage(IntToStr(i);/2f := MonthSpan(Now,Now+89);/差89天Showmessage(FloatToStr(f);/2.924End;MonthsBetween(返回两个指定日期间的月份数)引用单元:DateUtils函数声明:Function Months

27、Between ( const ANow, AThen : TDateTime) :Integer;MonthSpan(返回两个指定日期间的月份数)引用单元:DateUtils函数声明:Function MonthSpan ( const ANow, AThen : TDateTime) :Double;StartOfAMonth(返回特定年月的第一天)引用单元:DateUtils函数声明:Function StartOfAMonth ( const AYear, AMonth : Word) : TDateTime;EndOfAMonth(返回特定年月的最后一天)引用单元:DateUtils

28、函数声明:Function EndOfTheMonth ( const AYear, AMonth : Word) : TDateTime;StartOfTheMonth(返回特定年月的第一天)引用单元:DateUtils函数声明:Function StartOfTheMonth ( const AValue : TDateTime) :TDateTime;EndOfTheMonth(返回特定年月的最后一天)引用单元:DateUtils函数声明:Function EndOfTheMonth ( const AValue : TDateTime) :TDateTime;范例D-19varmyDa

29、teTime :TDateTime;Year,Month :Integer;BeginYear := YearOf(Now);Month :=MonthOf(Now);/找出当前月份的第一天myDateTime := StartOfAMonth(Year,Month);Showmessage(DateTimeToStr(myDateTime);/找出当前月份的最后一天myDateTime := EndOfAMonth(Year,Month);Showmessage(DateTimeToStr(myDateTime);/找出当前月份的第一天myDateTime := StartOfTheMont

30、h(Now);Showmessage(DateTimeToStr(myDateTime);/找出当前月份的最后一天myDateTime := EndOfTheMonth(Now);Showmessage(DateTimeToStr(myDateTime);end;IncMonth(指定的TDateTime变量加上指定的月份)引用单元:DateUtils函数声明:Function IncMonth ( const Date : TDateTime ; NumberOfMonths : Integer = 1) :TDateTime;IncAMonth(指定的年月日变量加上指定的月份)引用单元:D

31、ateUtils函数声明:Procedure IncAMonth ( Var Year, Month , Day : Word ; NumberOfMonths : Integer =1 );范例D-20varmyDateTime :TDateTime;Year,Month,Day :Word;Begin/加上指定的月份myDateTime := IncMonth(Now,3);/加上三个月Showmessage(DateTimeToStr(myDateTime);Year := YearOf(Now);Day := Dayof(Now);/加上指定的月份IncAMonth(Year,Mont

32、h,Day,3);Showmessage('Month'+IntToStr(Month);end ;DaysInAYear(返回指定年份的总天数)引用单元:DateUtils函数声明:Function DaysInAYear ( const AYear : Word) :Word;DaysInYear(返回指定TDateTime变量中该年份的总天数)引用单元:DateUtils函数声明:Function MinuteOfTheHour ( const AValue : TDateTime) :Word;DaysInAMonth(返回指定月份的总天数)引用单元:DateUtils

33、函数声明:Function DaysInAMonth ( const AYear , AMonth : Word) :Word;DaysInMonth(返回指定TDateTime变量中该月份的总天数)引用单元:DateUtils函数声明:Function DaysInMonth ( const AValue : TDateTime) :Word;范例D-21procedure TForm1.Button1Click(Sender : TObfect) ;varmyDateTime : TDateTime ;Year, Month : Word ;I : Integer ;BeginYear :

34、= YearOf(Now) ;/获取指定年份的总天数i := DaysInAYear(Year) ;Showmessage('DaysInAYear='+IntToStr (i) ;i := DaysInYear(now) ;Showmessage('DaysInMonth =' + IntToStr (i) ;/获取指定月份的总天数Month := MonthOf(Now) ;i := DaysInMonth(Now) ;Showmessage( 'DaysInMonth = '+IntToStr(i) ;end;DaysOf(获取TDateT

35、ime格式中的日期)引用单元:DateUtils函数声明:Function DaysOf ( const AValue : TDateTime) :Word;范例D-22procedure TForm1.Button1Click(Sender : TObfect) ;varDay : Word ;begin/获取指定TDateTime的日期Day := DayOf(Now) ;Showmessage(IntToStr(Day) ;end ;DaysBetween(返回两个指定日期间的天数)引用单元:DateUtils函数声明:Function DaysBetween( const ANow,

36、AThen : TDateTime) :Integer;DaySpan(返回两个指定日期间的天数)引用单元:DateUtils函数声明:Function DaySpan ( const ANow , AThen : TDateTime) :Double;范例D-23vari : Integer ;f : Double ;begin/获取两个日期的天数f:=DaySpan(Now-100 , Now) ;i := DaysBetween(Now-100 , Now) ;Showmessage(intToStr(i) ; /100Showmessage(FloatToStr(f) ; /100 e

37、nd ;DayOfTheYear(返回指定TDateTime变量为该年的第几天)引用单元:DateUtils函数声明:Function DayOfTheYear ( const AValue : TDateTime) :Word;DayOfTheMonth(返回指定TDateTime变量为该月的第几天)引用单元:DateUtils函数声明:Function DayOfTheMonth ( const AValue : TDateTime) :Word;DayOfTheWeek(返回指定TDateTime变量为该周的第几天)引用单元:DateUtils函数声明:Function DayOfThe

38、Week ( const AValue : TDateTime) :Word;DayOfWeek(返回指定TDateTime变量为该周的第几天)引用单元:DateUtils函数声明:Function DayOfWeek ( Date : TDateTime) :Integer;范例D-24procedure TForm1.Button1Click(Sender : TObfect) ;vari : Integer ;begin/返回指定TDateTime为该年的第几天i := DayOfTheYear(Now) ;Showmessage(IntToStr(i) ;/返回指定TDateTime为

39、该月的第几天i := DayOfTheMonth(Now) ;Showmessage(IntToStr(i) ;/返回指定TDateTime为该周的第几天(星期一为第一天)i := DayOfTheWeek(Now) ;Showmessage(IntToStr(i) ;end ;StartOfADay(返回指定日期一天的开始)引用单元:DateUtils函数声明:Function StartOfADay ( const AYear , AMonth, ADay : Word) :TDateTime;Function StartOfADay ( const AYear , ADayOfYear

40、: Word) :TDateTime;范例D-25procedure TForm1.Button1Click(Sender : TObfect) ;vartmpDateTime : TDateTime ;AYear , ADayOfYear , AMonth , ADay :Word ;beginAYear := 2001 ; /指定年度ADayOfYear := 32 ;./第32天tmpDateTime :=StartOfADay(AYear , ADayOfYear) ;Showmessage(DateTimeToStr(tmpDateTime) ; /2001/02/01AMonth

41、:= 1 ;ADay := 32 ; /从AMonth第一天起第32天TmpDateTime := StartOfADay(AYear , AMonth , ADay) ;Showmessage(DateTimeToStr(tmpDateTime) ; /2001/02/01end ;EndOfADay(返回指定日期一天的结束时间)引用单元:DateUtils函数声明:Function EndOfADay ( const AYear, AMonth,ADay : Word) : TDateTime;Function EndOfADay ( const AYear, ADayOfYear : W

42、ord) : TDateTime;范例D-26procedure TForm1.Button1Click(Sender : TObfect) ;vartmpDateTime : TDateTime ;AYear , ADayOfYear , AMonth , ADay : Word ;beginAYear := 2001 ; /指定年度ADayOfYear := 32 ; /第32天tmpDateTime := EndOfADay(AYear , AMonth , ADay) ;Showmessage(DateTimeToStr(tmpDateTime) ;/2001/02/01 PM 11:

43、59:59end ;StartOfTheDay(返回指定TDateTime变量的一天开始时间)引用单元:DateUtils函数声明:Function StartToTheDay ( const AValue : TDateTime) :TDateTime;EndOfTheDay(返回指定TDateTime变量的一天结束时间)引用单元:DateUtils函数声明:Function EndOfTheDay ( const AValue : TDateTime) : TDateTime;范例D-27procedure TForm1.Button1Click(Sender : TObfect) ;va

44、rtmpDateTime : TDateTime ;begintmpDateTime := StartOfTheDay(Now) ;Showmessage(DateTimeToStr(tmpDateTime) ;/YYYY/MM/DD AM 12:00:00tmpDateTime := EndOfTheDay(Now) ;Showmessage(DateTo /YYYY/MM/DD PM 11:59:59end ;IncDay(可为指定日期加上特定的天数)引用单元:DateUtils函数声明:Function IncDay ( const AValue : TDateTime ; const

45、ANumberOfDays : Integer =1) :TDateTime;范例D-28procedure TForm1.Button1Click(Sender : TObfect) ;vartmpDateTime : TDateTime ;begintmpDateTime := Incday(Now,5) ;Showmessage(DateTimeToStr(tmpDateTime) ;/时间部分并不会改变end ;WeeksInAYear(返回指定年度的周数)引用单元:DateUtils函数声明:Function WeeksInAYear( const AYear : Word) :Wo

46、rd;WeeksInYear(返回指定TDateTime变量的周数)引用单元:DateUtils函数声明:Function WeeksInYear ( const AValue : TDateTime) :Word;范例D-29procedure TForm1.Button1Click(Sender : TObfect) ;varweeks : word ;beginweeks :=weeksInAYear(2001) ;Showmessage(IntToStr(weeks) ; /52Weeks := WeeksInYear(Now) ;Showmessage(IntToStr(weeks)

47、 ; /52end ;WeeksOf(返回指定日期为该年的第几周)引用单元:DateUtils函数声明:Function WeekOf ( const AValue : TDateTime) :Word;WeekOfTheYear(返回指定日期为该年的第几周)引用单元:DateUtils函数声明:Function WeekOfTheYear ( const AValue : TDateTime) :Word;WeekOfTheMonth(返回指定日期为该月的第几周)引用单元:DateUtils函数声明:Function WeekOfTheMonth ( const AValue : TDate

48、Time) :Word;范例D-30Procedure TForm1.Button1Click(Sender: TObject);VarI : Word;BeginI :=WeekOf(Now);Showmessage('weekof=' + IntToStr(i); i := WeekOfTheYear(Now );Showmessage('WeekOfTheYear =' + IntToStr(i);I := WeekOfTheMonth(Now);Showmessage('WeekOfTheMonth=' + IntToStr(i); en

49、d;WeeksBetween(返回两个指定日期间的周数)引用单元:DateUtils函数声明:Function WeeksBetween ( const ANow , AThen, : TDateTime) :Integer;WeekSpan(返回两个指定日期间的周数)引用单元:DateUtils函数声明:Function WeekSpan( const ANow ,AThen : TDateTime) :Double;范例D-31Procedure TForm1.Button1Click(Sender: TObject);VarI : Integer;F :Double;BeginI :=W

50、eeksBetween(Now , Now + 29);Showmessage(InttoStr(i); /4F := WeekSpan(Now , Now + 29);Showmessage(FloatToStr(f); /4.14end;StartOfAWeek(返回指定日期一周的开始时间)引用单元:DateUtils函数声明:Function StartOfAWeek ( const AYear , AWeekOfYear : Word; const ADayOfWeek : Word = 1) : TDateTime;EndOfAWeek(返回指定日期一周的结束时间)引用单元:Date

51、Utils函数声明:Function EndOfAWeek ( const AYear , AWeekOfYear : Word; const ADayOfWeek : Word = 7) : TDateTime;范例D-32Procedure TForm1.Button1Click(Sender: TObject);VartempDateTime: TDateTime;AYear , AWeekOfYear , ADayOfWeek : Word;BeginAYear := 2001;AWeekOfYear :=2; /第二周ADayOfWeek :=1; /第一天tempDateTime

52、:= StartofAweek(AYear, AWeekOfYear, ADayOfWeek);/2001/01/08 AM 12:00:00:00showmessage(DateTimeToStr(tempDateTime);/AYearf := 2001;/AWeekofYear :=2; /第二周ADayOfWeek : =7 ;/ 第七天tempDatetime := EndOfAWeek(AYear, AWeekOfYear, AdayOfWeek);/2001/01/14 Pm 11:59:59Showmessage(DateTimeToStr(tempDateTime); /4.

53、14end;StartOfTheWeek(返回指定日期一周的开始时间)引用单元:DateUtils函数声明:Function StartOfTheWeek ( const AValue : TDateTime) :TDateTime;EndOfTheWeek(返回指定日期一周的结束时间)引用单元:DateUtils函数声明:Function EndOfTheWeek ( const AValue : TDateTime) :TDateTime;范例D-33Procedure TForm1.Button1Click(Sender: TObject);VartempDateTime : TDate

54、Time;begintempDateTime :=StartOfTheWeek(Now);/YYYY / MM / DD AM 12:00:00:00Showmessage(DateTimeToStr(tempDateTime);tempDateTime := EndOfTheWeek(Now);/YYYY / MM / DD + 6 PM 11:59 :59Showmessage(DateTimeToStr(tempDateTime);end;IncWeek(将指定日期加上指定周数)引用单元:DateUtils函数声明:Function IncWeek ( const AValue : TD

55、ateTime; const ANumberOfWeeks : Integer = 1) :TDateTime;范例D-34:Procedure TForm1.Button1Click(Sender: TObject);VartempDateTime : TDateTime;begintempDateTime :=IncWeek(Now , 5); /加上5周Showmessage(DateTimeToStr(tempDateTime);end;D.3 时间处理函数函数名称单元文件所代表的意义HoursBetweenDateUtils此函数可返回两个指定TDateTime变量间的小时数,返回值不包含小数部分.HourSpanDateUtils此函数可返回