有没有获得当前月份上个月的函数？？？
如当前月份为12月，要获得11月。 问题点数：0、回复次数：15Top
1 楼outer2000（天外流星）回复于 2003-12-18 11:58:15 得分 0
Returns a date shifted by a specified number of months.
Unit
SysUtils
Category
datetime routines
Delphi syntax:
function IncMonth(const Date: TDateTime; NumberOfMonths: Integer = 1): TDateTime;
C++ syntax:
extern PACKAGE System::TDateTime __fastcall IncMonth(const System::TDateTime Date, int NumberOfMonths = 1);
Description
IncMonth returns the value of the Date parameter, incremented by NumberOfMonths months. NumberOfMonths can be negative, to return a date N months previous.
If the input day of month is greater than the last day of the resulting month, the day is set to the last day of the resulting month. The time of day specified by the Date parameter is copied to the result.Top
2 楼8009000077（）回复于 2003-12-18 12:00:36 得分 0
incMonth()Top
3 楼angle097113（深思不解）回复于 2003-12-18 12:08:07 得分 0
我一般是获得当前的月份 然后减1实现得Top
4 楼aiirii（ari-http://spaces.msn.com/members/aiirii/）回复于 2003-12-18 12:08:07 得分 0
uses DateUtils
MonthOf(now) - 1Top
5 楼gencan（无敌）回复于 2003-12-18 12:27:30 得分 0
MonthOf(now) - 1
Top
6 楼nxfbccu（杀缺衣）回复于 2003-12-18 12:34:36 得分 0
uses DateUtils
MonthOf(now) - 1
Top
7 楼aiirii（ari-http://spaces.msn.com/members/aiirii/）回复于 2003-12-18 12:37:20 得分 0
i := MonthOf(now) - 1;
if i = 0 then i := 12;
Top
8 楼rst_2828（海岛管理员）回复于 2003-12-18 13:44:03 得分 0
uses DateUtils
提示"file not found:'DateUtils.dcu'",怎么办啊？Top
9 楼aiirii（ari-http://spaces.msn.com/members/aiirii/）回复于 2003-12-18 13:47:04 得分 0
你有的是delphi 几啊?? 你在那裹uses???Top
10 楼rst_2828（海岛管理员）回复于 2003-12-18 13:52:06 得分 0
delphi 5
我在interface后面usesTop
11 楼zzllabc（抱朴子--清心释累，绝率忘情）回复于 2003-12-18 14:02:01 得分 0
Delphi 5没有这个单元，这个函数是6里的。Top
12 楼zzllabc（抱朴子--清心释累，绝率忘情）回复于 2003-12-18 14:04:26 得分 0
{ *********************************************************************** }
{ }
{ Delphi Runtime Library }
{ }
{ Copyright (c) 1995-2001 Borland Software Corporation }
{ }
{ *********************************************************************** }
{*******************************************************}
{ Date/time Utilities Unit }
{*******************************************************}
{ The following unit is ISO 8601 compliant. What that means is this unit
considers Monday the first day of the week (5.2.3). Additionally ISO 8601
dictates the following "the first calendar week of the year is the one
that includes the first Thursday of that year" (3.17). In other words the
first week of the week is the first one that has four or more days. For
more information about ISO 8601 see: http://www.iso.ch/markete/8601.pdf
The functions most impacted by ISO 8601 are marked as such in the interface
section.
The functions marked with "ISO 8601x" are not directly covered by ISO 8601
but their functionality is a logical extension to the standard.
Some of the functions, concepts or constants in this unit were provided by
Jeroen W. Pluimers (http://www.all-im.com), Glenn Crouch, Rune Moberg and
Ray Lischner (http://www.tempest-sw.com).
The Julian Date and Modified Julian Date functions are based on code
from NASA's SOHO site (http://sohowww.nascom.nasa.gov/solarsoft/gen/idl/time)
in which they credit the underlying algorithms as by Fliegel and Van
Flandern (1968) which was reprinted in the Explanatory Supplement to the
Astronomical Almanac, 1992.
Julian Date and Modified Julian Date is discussed in some detail on the
US Naval Observatory Time Service site (http://tycho.usno.navy.mil/mjd.html).
Additional information can be found at (http://www.treasure-troves.com/astro).
}
unit DateUtils;
interface
uses
SysUtils, Math, Types;
{ Simple trimming functions }
function DateOf(const AValue: TDateTime): TDateTime;
function TimeOf(const AValue: TDateTime): TDateTime;
{ Misc functions }
function IsInLeapYear(const AValue: TDateTime): Boolean;
function IsPM(const AValue: TDateTime): Boolean;
function IsValidDate(const AYear, AMonth, ADay: Word): Boolean;
function IsValidTime(const AHour, AMinute, ASecond, AMilliSecond: Word): Boolean;
function IsValidDateTime(const AYear, AMonth, ADay, AHour, AMinute, ASecond,
AMilliSecond: Word): Boolean;
function IsValidDateDay(const AYear, ADayOfYear: Word): Boolean;
function IsValidDateWeek(const AYear, AWeekOfYear, {ISO 8601}
ADayOfWeek: Word): Boolean;
function IsValidDateMonthWeek(const AYear, AMonth, AWeekOfMonth, {ISO 8601x}
ADayOfWeek: Word): Boolean;
function WeeksInYear(const AValue: TDateTime): Word; {ISO 8601}
function WeeksInAYear(const AYear: Word): Word; {ISO 8601}
function DaysInYear(const AValue: TDateTime): Word;
function DaysInAYear(const AYear: Word): Word;
function DaysInMonth(const AValue: TDateTime): Word;
function DaysInAMonth(const AYear, AMonth: Word): Word;
function Today: TDateTime;
function Yesterday: TDateTime;
function Tomorrow: TDateTime;
function IsToday(const AValue: TDateTime): Boolean;
function IsSameDay(const AValue, ABasis: TDateTime): Boolean;
{ Pick-a-field functions }
function YearOf(const AValue: TDateTime): Word;
function MonthOf(const AValue: TDateTime): Word;
function WeekOf(const AValue: TDateTime): Word; {ISO 8601}
function DayOf(const AValue: TDateTime): Word;
function HourOf(const AValue: TDateTime): Word;
function MinuteOf(const AValue: TDateTime): Word;
function SecondOf(const AValue: TDateTime): Word;
function MilliSecondOf(const AValue: TDateTime): Word;
{ Start/End functions }
function StartOfTheYear(const AValue: TDateTime): TDateTime;
function EndOfTheYear(const AValue: TDateTime): TDateTime;
function StartOfAYear(const AYear: Word): TDateTime;
function EndOfAYear(const AYear: Word): TDateTime;
function StartOfTheMonth(const AValue: TDateTime): TDateTime;
function EndOfTheMonth(const AValue: TDateTime): TDateTime;
function StartOfAMonth(const AYear, AMonth: Word): TDateTime;
function EndOfAMonth(const AYear, AMonth: Word): TDateTime;
function StartOfTheWeek(const AValue: TDateTime): TDateTime; {ISO 8601}
function EndOfTheWeek(const AValue: TDateTime): TDateTime; {ISO 8601}
function StartOfAWeek(const AYear, AWeekOfYear: Word; {ISO 8601}
const ADayOfWeek: Word = 1): TDateTime;
function EndOfAWeek(const AYear, AWeekOfYear: Word; {ISO 8601}
const ADayOfWeek: Word = 7): TDateTime;
function StartOfTheDay(const AValue: TDateTime): TDateTime;
function EndOfTheDay(const AValue: TDateTime): TDateTime;
function StartOfADay(const AYear, AMonth, ADay: Word): TDateTime; overload;
function EndOfADay(const AYear, AMonth, ADay: Word): TDateTime; overload;
function StartOfADay(const AYear, ADayOfYear: Word): TDateTime; overload;
function EndOfADay(const AYear, ADayOfYear: Word): TDateTime; overload;
{ This of that functions }
Top
13 楼zzllabc（抱朴子--清心释累，绝率忘情）回复于 2003-12-18 14:05:56 得分 0
function MonthOfTheYear(const AValue: TDateTime): Word;
function WeekOfTheYear(const AValue: TDateTime): Word; overload; {ISO 8601}
function WeekOfTheYear(const AValue: TDateTime; {ISO 8601}
var AYear: Word): Word; overload;
function DayOfTheYear(const AValue: TDateTime): Word;
function HourOfTheYear(const AValue: TDateTime): Word;
function MinuteOfTheYear(const AValue: TDateTime): LongWord;
function SecondOfTheYear(const AValue: TDateTime): LongWord;
function MilliSecondOfTheYear(const AValue: TDateTime): Int64;
function WeekOfTheMonth(const AValue: TDateTime): Word; overload; {ISO 8601x}
function WeekOfTheMonth(const AValue: TDateTime; var AYear, {ISO 8601x}
AMonth: Word): Word; overload;
function DayOfTheMonth(const AValue: TDateTime): Word;
function HourOfTheMonth(const AValue: TDateTime): Word;
function MinuteOfTheMonth(const AValue: TDateTime): Word;
function SecondOfTheMonth(const AValue: TDateTime): LongWord;
function MilliSecondOfTheMonth(const AValue: TDateTime): LongWord;
function DayOfTheWeek(const AValue: TDateTime): Word; {ISO 8601}
function HourOfTheWeek(const AValue: TDateTime): Word; {ISO 8601}
function MinuteOfTheWeek(const AValue: TDateTime): Word; {ISO 8601}
function SecondOfTheWeek(const AValue: TDateTime): LongWord; {ISO 8601}
function MilliSecondOfTheWeek(const AValue: TDateTime): LongWord; {ISO 8601}
function HourOfTheDay(const AValue: TDateTime): Word;
function MinuteOfTheDay(const AValue: TDateTime): Word;
function SecondOfTheDay(const AValue: TDateTime): LongWord;
function MilliSecondOfTheDay(const AValue: TDateTime): LongWord;
function MinuteOfTheHour(const AValue: TDateTime): Word;
function SecondOfTheHour(const AValue: TDateTime): Word;
function MilliSecondOfTheHour(const AValue: TDateTime): LongWord;
function SecondOfTheMinute(const AValue: TDateTime): Word;
function MilliSecondOfTheMinute(const AValue: TDateTime): LongWord;
function MilliSecondOfTheSecond(const AValue: TDateTime): Word;
{ Range checking functions }
function WithinPastYears(const ANow, AThen: TDateTime;
const AYears: Integer): Boolean;
function WithinPastMonths(const ANow, AThen: TDateTime;
const AMonths: Integer): Boolean;
function WithinPastWeeks(const ANow, AThen: TDateTime;
const AWeeks: Integer): Boolean;
function WithinPastDays(const ANow, AThen: TDateTime;
const ADays: Integer): Boolean;
function WithinPastHours(const ANow, AThen: TDateTime;
const AHours: Int64): Boolean;
function WithinPastMinutes(const ANow, AThen: TDateTime;
const AMinutes: Int64): Boolean;
function WithinPastSeconds(const ANow, AThen: TDateTime;
const ASeconds: Int64): Boolean;
function WithinPastMilliSeconds(const ANow, AThen: TDateTime;
const AMilliSeconds: Int64): Boolean;
{ Range query functions }
function YearsBetween(const ANow, AThen: TDateTime): Integer;
function MonthsBetween(const ANow, AThen: TDateTime): Integer;
function WeeksBetween(const ANow, AThen: TDateTime): Integer;
function DaysBetween(const ANow, AThen: TDateTime): Integer;
function HoursBetween(const ANow, AThen: TDateTime): Int64;
function MinutesBetween(const ANow, AThen: TDateTime): Int64;
function SecondsBetween(const ANow, AThen: TDateTime): Int64;
function MilliSecondsBetween(const ANow, AThen: TDateTime): Int64;
{ Range spanning functions }
{ YearSpan and MonthSpan are approximates, not exact but pretty darn close }
function YearSpan(const ANow, AThen: TDateTime): Double;
function MonthSpan(const ANow, AThen: TDateTime): Double;
function WeekSpan(const ANow, AThen: TDateTime): Double;
function DaySpan(const ANow, AThen: TDateTime): Double;
function HourSpan(const ANow, AThen: TDateTime): Double;
function MinuteSpan(const ANow, AThen: TDateTime): Double;
function SecondSpan(const ANow, AThen: TDateTime): Double;
function MilliSecondSpan(const ANow, AThen: TDateTime): Double;
{ Increment/decrement datetime fields }
function IncYear(const AValue: TDateTime;
const ANumberOfYears: Integer = 1): TDateTime;
// function IncMonth is in SysUtils
function IncWeek(const AValue: TDateTime;
const ANumberOfWeeks: Integer = 1): TDateTime;
function IncDay(const AValue: TDateTime;
const ANumberOfDays: Integer = 1): TDateTime;
function IncHour(const AValue: TDateTime;
const ANumberOfHours: Int64 = 1): TDateTime;
function IncMinute(const AValue: TDateTime;
const ANumberOfMinutes: Int64 = 1): TDateTime;
function IncSecond(const AValue: TDateTime;
const ANumberOfSeconds: Int64 = 1): TDateTime;
function IncMilliSecond(const AValue: TDateTime;
const ANumberOfMilliSeconds: Int64 = 1): TDateTime;
{ Unified encode/decode functions that deal with all datetime fields at once }
function EncodeDateTime(const AYear, AMonth, ADay, AHour, AMinute, ASecond,
AMilliSecond: Word): TDateTime;
procedure DecodeDateTime(const AValue: TDateTime; out AYear, AMonth, ADay,
AHour, AMinute, ASecond, AMilliSecond: Word);
{ Encode/decode functions that work with week of year and day of week }
function EncodeDateWeek(const AYear, AWeekOfYear: Word; {ISO 8601}
const ADayOfWeek: Word = 1): TDateTime;
procedure DecodeDateWeek(const AValue: TDateTime; out AYear, {ISO 8601}
AWeekOfYear, ADayOfWeek: Word);
{ Encode/decode functions that work with day of year }
function EncodeDateDay(const AYear, ADayOfYear: Word): TDateTime;
procedure DecodeDateDay(const AValue: TDateTime; out AYear, ADayOfYear: Word);
{ Encode/decode functions that work with week of month }
function EncodeDateMonthWeek(const AYear, AMonth, AWeekOfMonth, {ISO 8601x}
ADayOfWeek: Word): TDateTime;
procedure DecodeDateMonthWeek(const AValue: TDateTime; {ISO 8601x}
out AYear, AMonth, AWeekOfMonth, ADayOfWeek: Word);
{ The following functions are similar to the above ones except these don't
generated exceptions on failure, they return false instead }
function TryEncodeDateTime(const AYear, AMonth, ADay, AHour, AMinute, ASecond,
AMilliSecond: Word; out AValue: TDateTime): Boolean;
function TryEncodeDateWeek(const AYear, AWeekOfYear: Word; {ISO 8601}
out AValue: TDateTime; const ADayOfWeek: Word = 1): Boolean;
function TryEncodeDateDay(const AYear, ADayOfYear: Word;
out AValue: TDateTime): Boolean;
function TryEncodeDateMonthWeek(const AYear, AMonth, AWeekOfMonth, {ISO 8601x}
ADayOfWeek: Word; var AValue: TDateTime): Boolean;
Top
14 楼xinshiji（自由我有）回复于 2003-12-18 14:06:58 得分 0
uses DateUtils
MonthOf(now) - 1
Top
15 楼zzllabc（抱朴子--清心释累，绝率忘情）回复于 2003-12-18 14:08:02 得分 0
>>>连续的回复不能超过3次
Sorry,本想把这个单元给你贴上来，却不让连续回复，只有你自己去找了。Top
