Date 传回目前的日期Unit SysUtils函数原型 function Date: TDateTime;范例 procedure TForm1.Button1Click(Sender: TObject); begin Label1.Caption := 'Today is ' + DateToStr(Date); end;------------------------------------------DateTimeToStr 日期时间转换成内定型字串(1996/12/20 09:12:20 PM)------------------------------------------Unit SysUtils函数原型 function DateTimeToStr(DateTime: TDateTime): string;范例 procedure TForm1.Button1Click(Sender: TObject); begin Label1.Caption := DateTimeToStr(Now); end;--------------------------------------------------------DateTimeToString 日期时间转换成自定型字串-------------------------------------------------------Unit SysUtils函数原型 procedure DateTimeToString(var Result: string; const Format: string; DateTime: TDateTime);范例 procedure TForm1.FormCreate(Sender: TObject); var s:string; begin DateTimeToString(s,'dddd,mmmm d,yyyy "at" hh:mm AM/PM',Now); Label1.Caption :=s; end;结果 星期五,十二月 20,1996 at 09:20 PM-----------------------------------------------------------------------------**** Format格式叁考下面.FormatDateTime.--------------------------------------------------------DateToStr 日期转换成内定型字串.(1996/12/20)--------------------------------------------------------Unit SysUtils函数原型 function DateToStr(Date: TDateTime): string;范例procedure TForm1.Button1Click(Sender: TObject);begin Label1.Caption := 'Today is ' + DateToStr(Date);end;# Date, DateToStr Example--------------------------------------------------------DayOfWeek 求叁数日期是星期几.--------------------------------------------------------Unit SysUtils函数原型 function DayOfWeek(Date: TDateTime): Integer;说明 传回值是一整数,1~7. 星期日为1.范例procedure TForm1.Button1Click(Sender: TObject);var ADate: TDateTime; days: array[1..7] of string;begin days[1] := 'Sunday'; days[2] := 'Monday'; days[3] := 'Tuesday'; days[4] := 'Wednesday'; days[5] := 'Thursday'; days[6] := 'Friday'; days[7] := 'Saturday'; ADate := StrToDate(Edit1.Text); ShowMessage(Edit1.Text + ' is a ' + days[DayOfWeek(ADate)];end;# StrToDate, DayOfWeek Example--------------------------------------------------------DecodeDate 将TDateTime型态的日期变数，转为Word型态.--------------------------------------------------------范例procedure TForm1.Button1Click(Sender: TObject);var Present: TDateTime; Year, Month, Day, Hour, Min, Sec, MSec: Word; begin Present:= Now; DecodeDate(Present, Year, Month, Day); Label1.Caption := 'Today is Day ' + IntToStr(Day) + ' of Month ' + IntToStr(Month) + ' of Year ' + IntToStr(Year); DecodeTime(Present, Hour, Min, Sec, MSec); Label2.Caption := 'The time is Minute ' + IntToStr(Min) + ' of Hour ' + IntToStr(Hour);end;# DecodeDate, DecodeTime Example--------------------------------------------------------DecodeTime 将TDateTime型态的时间变数，转为Word型态.--------------------------------------------------------Unit SysUtils函数原型 procedure DecodeDate(Date: TDateTime; var Year, Month,Day: Word);函数原型 procedure DecodeTime(Time: TDateTime; var Hour, Min, Sec,MSec: Word);范例 procedure TForm1.Button1Click(Sender: TObject); var Present: TDateTime; Year, Month, Day, Hour, Min, Sec, MSec: Word; begin Present:= Now; DecodeDate(Present, Year, Month, Day); Label1.Caption := 'Today is Day ' + IntToStr(Day) + ' of Month ' + IntToStr(Month) + ' of Year ' + IntToStr(Year); DecodeTime(Present, Hour, Min, Sec, MSec); Label2.Caption := 'The time is Minute ' +IntToStr(Min) + ' of Hour ' + IntToStr(Hour); end;--------------------------------------------------------EncodeDate 将Word型态的日期变数，转为TDateTime型态.--------------------------------------------------------范例procedure TForm1.Button1Click(Sender: TObject);var MyDate: TDateTime;begin MyDate := EncodeDate(StrToInt(Edit1.Text), StrToInt(Edit2.Text), StrToInt(Edit3.Text)); Label1.Caption := DateToStr(MyDate);end;-------------------------------------------------------EncodeTime 将Word型态的时间变数，转为TDateTime型态.--------------------------------------------------------Unit SysUtils函数原型 function EncodeDate(Year, Month, Day: Word): TDateTime;函数原型 function EncodeTime(Hour, Min, Sec, MSec: Word): TDateTime;范例 procedure TForm1.Button1Click(Sender: TObject); var MyDate: TDateTime; MyTime: TDateTime; begin MyDate := EncodeDate(83, 12, 31); Label1.Caption := DateToStr(MyDate); MyTime := EncodeTime(0, 45, 45, 7); Label2.Caption := TimeToStr(MyTime); end;范例procedure TForm1.Button1Click(Sender: TObject);var MyTime: TDateTime;begin MyTime := EncodeTime(0, 45, 45, 7); Label1.Caption := TimeToStr(MyTime);end;--------------------------------------------------------FormatDateTime 将日期时间依Format的格式转换给一字串.--------------------------------------------------------Unit SysUtils函数原型 function FormatDateTime(const Format: string; DateTime: TDateTime): string;**** 类似DateTimeToString.Format格式c 内定值ShortDateFormat的格式.(1996/12/20 09:20:15 PM).d 日期,前面不补0.(1-31)dd 日期,前面补0.(01-31)ddd 星期.(星期日).Dddd 中文2.01版,同上.ddddd 日期.(1996/12/20)dddddd 日期.(1996年12月20日)m 月份,前面不补0.(1-12)mm 月份,前面补0.(01-12)mmm 中文显示.(十二月)mmmm 中文2.01版,同上.Yy 年度.(00-99)yyyy 年度.(0000-9999)h 小时.(0-23)hh 小时.(00-23)n 分钟.(0-59)nn 分钟.(00-59)s 秒钟.(0-59)ss 秒钟.(00-59)t 时间.(09:20 PM)tt 时间.(09:20:15 PM)am/pm 单独显示am or pm.(若大写,则显示大写)a/p 单独显示a or p.范例The following example assigns 'The meeting is on Wednesday, February 15, 1995 at 10:30 AM' to the string variable S. S := FormatDateTime('"The meeting is on " dddd, mmmm d, yyyy, " at " hh:mm AM/PM', StrToDateTime('2/15/95 10:30am'));//???--------------------------------------------------------Now 传回目前的日期时间.--------------------------------------------------------Unit SysUtils函数原型 function Now: TDateTime;范例procedure TForm1.Button1Click(Sender: TObject);begin Label1.Caption := DateTimeToStr(Now);end;# Now, DateTimeToStr Example--------------------------------------------------------StrToDate 将字串转为TDateTime型态的日期.--------------------------------------------------------Unit SysUtils函数原型 function StrToDate(const S: string): TDateTime;范例 procedure TForm1.Button1Click(Sender: TObject); var ADate: TDateTime; begin ADate := StrToDate(Edit1.Text); Label1.Caption := DateToStr(ADate); end;范例procedure TForm1.Button1Click(Sender: TObject);var ADate: TDateTime; days: array[1..7] of string;begin days[1] := 'Sunday'; days[2] := 'Monday'; days[3] := 'Tuesday'; days[4] := 'Wednesday'; days[5] := 'Thursday'; days[6] := 'Friday'; days[7] := 'Saturday'; ADate := StrToDate(Edit1.Text); ShowMessage(Edit1.Text + ' is a ' + days[DayOfWeek(ADate)];end;# StrToDate, DayOfWeek Example--------------------------------------------------------StrToDateTime 将字串转为TDateTime型态的日期时间.--------------------------------------------------------Unit SysUtils函数原型 function StrToDateTime(const S: string): TDateTime;范例procedure TForm1.Button1Click(Sender: TObject);var ADateAndTime: TDateTime;begin ADateAndTime := StrToDateTime(Edit1.Text); Table1.FieldByName('TimeStamp').AsDateTime := ADateAndTime;end;--------------------------------------------------------StrToTime 将字串转为TDateTime型态的时间.--------------------------------------------------------Unit SysUtils函数原型 function StrToTime(const S: string): TDateTime;范例procedure TForm1.Button1Click(Sender: TObject);var ATime: TDateTime;begin ATime := StrToTime(Edit1.Text); if ATime < 0.50 then ShowMessage('Good Morning') else ShowMessage('Good Afternoon');end;--------------------------------------------------------Time 传回目前的时间.--------------------------------------------------------Unit SysUtils函数原型 function Time: TDateTime;范例procedure TForm1.Timer1Timer(Sender: TObject);var DateTime : TDateTime; str : string;begin DateTime := Time; // store the current date and time str := TimeToStr(DateTime); // convert the time into a string Caption := str; // display the time on the form's caption { Note This could have been done with the following line of code: Caption := TimeToStr(Time); }end;# Time, TimeToStr Example--------------------------------------------------------TimeToStr 时间转换成内定型字串.(09:20:15 PM)--------------------------------------------------------Unit SysUtils函数原型 function TimeToStr(Time: TDateTime): string; GetMem procedure 配置记忆体程序New 配置指位器P的记忆体空间， 大小为P所指型态的大小.--------------------------------------------------------Dispose 释放New所配置的记忆体.--------------------------------------------------------Unit System函数原型 procedure New(var P: Pointer);函数原型 procedure Dispose(var P: Pointer);范例 type PListEntry = ^TListEntry; TListEntry = record Next: PListEntry; Text: string; Count: Integer; end; var List, P: PListEntry; begin ... New(P); P^.Next := List; P^.Text := 'Hello world'; P^.Count := 1; List := P; ... Dispose(P); … end;范例type Str18 = string[18]; var P: ^Str18;begin New(P); P^ := 'Now you see it...'; Dispose(P); { Now you don't... }end;--------------------------------------------------------GetMem 配置指位器P的记忆体空间，大小可自行设定.--------------------------------------------------------范例var F: file; Size: Integer; Buffer: PChar;begin AssignFile(F, 'test.txt'); Reset(F, 1); try Size := FileSize(F); GetMem(Buffer, Size); try BlockRead(F, Buffer^, Size); ProcessFile(Buffer, Size); finally FreeMem(Buffer); end; finally CloseFile(F); end;end;系统相关的常用时间函数几乎都在这了.你问的问题每个准.只能这么答了.
