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WithinPastDays function

In unit DateUtils

Check whether two TDateTimes are only a number of days apart.

Declaration

pascal
function WithinPastDays(const ANow: TDateTime; const AThen: TDateTime; 
 const ADays: Integer): Boolean

Arguments

ANow

First moment in time.

AThen

Second moment in time.

ADays

Number of days to check.

Function result

True if ANow and Athen are only ADays apart, false otherwise.

Description

WithinPastDays compares the timestamps ANow and AThen and returns True if the difference between them is at most ADays days apart, or False if they are further apart.

Since this function uses the DaysBetween function to calculate the difference in days, this means that fractional days do not count, and the fractional part is simply dropped, so for two dates actually 2 and a half days apart, the result will also be True

See also

Example: ex50

pascal
Program Example50;

{ This program demonstrates the WithinPastDays function }

Uses SysUtils,DateUtils;

Procedure Test(ANow,AThen : TDateTime; ADays : Integer);

begin
 Write(DateTimeToStr(AThen),' and ',DateTimeToStr(ANow));
 Write(' are within ',ADays,' days: ');
 Writeln(WithinPastDays(ANow,AThen,ADays));
end;

Var
  D1,D2 : TDateTime;

Begin
  D1:=Now;
  D2:=Today-23/24;
  Test(D1,D2,1);
  D2:=Today-1;
  Test(D1,D2,1);
  D2:=Today-25/24;
  Test(D1,D2,1);
  D2:=Today-26/24;
  Test(D1,D2,5);
  D2:=Today-5.4;
  Test(D1,D2,5);
  D2:=Today-2.5;
  Test(D1,D2,1);
  Test(D1,D2,2);
  Test(D1,D2,3);
End.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.