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WithinPastHours function

In unit DateUtils

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

Declaration

pascal
function WithinPastHours(const ANow: TDateTime; const AThen: TDateTime; 
 const AHours: Int64): Boolean

Arguments

ANow

First moment in time.

AThen

Second moment in time.

AHours

Number of hours to check.

Function result

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

Description

WithinPastHours compares the timestamps ANow and AThen and returns True if the difference between them is at most AHours hours apart, or False if they are further apart.

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

See also

Example: ex51

pascal
Program Example51;

{ This program demonstrates the WithinPastHours function }

Uses SysUtils,DateUtils;

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

begin
 Write(DateTimeToStr(AThen),' and ',DateTimeToStr(ANow));
 Write(' are within ',AHours,' hours: ');
 Writeln(WithinPastHours(ANow,AThen,AHours));
end;

Var
  D1,D2 : TDateTime;

Begin
  D1:=Now;
  D2:=D1-(59*OneMinute);
  Test(D1,D2,1);
  D2:=D1-(61*OneMinute);
  Test(D1,D2,1);
  D2:=D1-(122*OneMinute);
  Test(D1,D2,1);
  D2:=D1-(306*OneMinute);
  Test(D1,D2,5);
  D2:=D1-(5.4*OneHour);
  Test(D1,D2,5);
  D2:=D1-(2.5*OneHour);
  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.