DateOf、TimeOf、YearOf、MonthOf、WeekOf、DayOf、HourOf、MinuteOf、SecondOf、MilliSecondOf - 提取时间成分

它们的参数都是一个 TDateTime,
DateOf、TimeOf 分别提取日期与时间, 并返回 TDateTime 类型;
YearOf、MonthOf、WeekOf、DayOf、HourOf、MinuteOf、SecondOf、MilliSecondOf 返回的都是 Word 类型.

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unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs;

type
  TForm1 = class(TForm)
    procedure FormCreate(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

uses DateUtils;

procedure TForm1.FormCreate(Sender: TObject);
var
  dt,d,t: TDateTime;
  Year,Month,Week,Day,Hour,Minute,Second,MilliSecond: Word;
begin
  dt := StrToDateTime('2009-5-20 11:22:33');

  d := DateOf(dt);
  ShowMessage(DateToStr(d)); //2009-5-20

  t := TimeOf(dt);
  ShowMessage(TimeToStr(t)); //11:22:33

  Year        := YearOf(dt);
  Month       := MonthOf(dt);
  Week        := WeekOf(dt);
  Day         := DayOf(dt);
  Hour        := HourOf(dt);
  Minute      := MinuteOf(dt);
  Second      := SecondOf(dt);
  MilliSecond := MilliSecondOf(dt);

  ShowMessageFmt('%d,%d,%d,%d,%d,%d,%d,%d', [Year,Month,Week,Day,Hour,Minute,
    Second,MilliSecond]); {2009,5,20,11,22,33,0}
end;

end.

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DateUtils-Function

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