StartOfAYear ... StartOfTheYear ... EndOfAYear ... EndOfTheYear ... 每年、月、周、日的开始与结束的时间

{参数是指定的年、月、周、日}

DateUtils.StartOfAYear 

DateUtils.StartOfAMonth

DateUtils.StartOfAWeek 

DateUtils.StartOfADay



{参数是 TDateTime}

DateUtils.StartOfTheYear 

DateUtils.StartOfTheMonth

DateUtils.StartOfTheWeek 

DateUtils.StartOfTheDay



{参数是指定的年、月、周、日}

DateUtils.EndOfAYear 

DateUtils.EndOfAMonth

DateUtils.EndOfAWeek 

DateUtils.EndOfADay



{参数是 TDateTime}

DateUtils.EndOfTheYear

DateUtils.EndOfTheMonth

DateUtils.EndOfTheWeek

DateUtils.EndOfTheDay


 
   

unit Unit1;



interface



uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls;



type

  TForm1 = class(TForm)

    procedure FormCreate(Sender: TObject);

  end;



var

  Form1: TForm1;



implementation



{$R *.dfm}



uses DateUtils;



procedure TForm1.FormCreate(Sender: TObject);

var

  dt,t1,t2,t3,t4: TDateTime;

  s1,s2,s3,s4: string;

begin

  dt := StrToDateTime('2009-5-20 11:22:33');



  t1 := StartOfAYear(2009);

  t2 := StartOfTheYear(dt);

  t3 := EndOfAYear(2009);

  t4 := EndOfTheYear(dt);



  s1 := FormatDateTime('yyyy-m-d h:n:s:zzz', t1); //2009-1-1 0:0:0:000

  s2 := FormatDateTime('yyyy-m-d h:n:s:zzz', t2); //2009-1-1 0:0:0:000

  s3 := FormatDateTime('yyyy-m-d h:n:s:zzz', t3); //2009-12-31 23:59:59:999

  s4 := FormatDateTime('yyyy-m-d h:n:s:zzz', t4); //2009-12-31 23:59:59:999



  t1 := StartOfAMonth(2009, 5); { 2009 年 5 月 }

  t2 := StartOfTheMonth(dt);

  t3 := EndOfAMonth(2009, 5);

  t4 := EndOfTheMonth(dt);



  s1 := FormatDateTime('yyyy-m-d h:n:s:zzz', t1); //2009-5-1 0:0:0:000

  s2 := FormatDateTime('yyyy-m-d h:n:s:zzz', t2); //2009-5-1 0:0:0:000

  s3 := FormatDateTime('yyyy-m-d h:n:s:zzz', t3); //2009-5-31 23:59:59:999

  s4 := FormatDateTime('yyyy-m-d h:n:s:zzz', t4); //2009-5-31 23:59:59:999





  t1 := StartOfAWeek(2009, 21); { 2009 年第 21 周 }

  t2 := StartOfTheWeek(dt);

  t3 := EndOfAWeek(2009, 21);

  t4 := EndOfTheWeek(dt);



  s1 := FormatDateTime('yyyy-m-d h:n:s:zzz', t1); //2009-5-18 0:0:0:000

  s2 := FormatDateTime('yyyy-m-d h:n:s:zzz', t2); //2009-5-18 0:0:0:000

  s3 := FormatDateTime('yyyy-m-d h:n:s:zzz', t3); //2009-5-24 23:59:59:999

  s4 := FormatDateTime('yyyy-m-d h:n:s:zzz', t4); //2009-5-24 23:59:59:999



  t1 := StartOfADay(2009, 140); { 2009 年第 140 天 }

  t2 := StartOfTheDay(dt);

  t3 := EndOfADay(2009, 140);

  t4 := EndOfTheDay(dt);



  s1 := FormatDateTime('yyyy-m-d h:n:s:zzz', t1); //2009-5-20 0:0:0:000

  s2 := FormatDateTime('yyyy-m-d h:n:s:zzz', t2); //2009-5-20 0:0:0:000

  s3 := FormatDateTime('yyyy-m-d h:n:s:zzz', t3); //2009-5-20 23:59:59:999

  s4 := FormatDateTime('yyyy-m-d h:n:s:zzz', t4); //2009-5-20 23:59:59:999

end;



end.

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DateUtils-Function

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