Sign in Join
FPDoc Onlineexperiment

WithinPastSeconds function

In unit DateUtils

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

Declaration

pascal
function WithinPastSeconds(const ANow: TDateTime; 
 const AThen: TDateTime; const ASeconds: Int64)
: Boolean

Arguments

ANow

First moment in time.

AThen

Second moment in time.

ASeconds

Number of seconds to check.

Function result

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

Description

WithinPastSeconds compares the timestamps ANow and AThen and returns True if the difference between them is at most ASeconds seconds apart, or False if they are further apart.

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

See also

Example: ex53

pascal
Program Example53;

{ This program demonstrates the WithinPastSeconds function }

Uses SysUtils,DateUtils;

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

begin
 Write(DateTimeToStr(AThen),' and ',DateTimeToStr(ANow));
 Write(' are within ',ASeconds,' seconds: ');
 Writeln(WithinPastSeconds(ANow,AThen,ASeconds));
end;

Var
  D1,D2 : TDateTime;

Begin
  D1:=Now;
  D2:=D1-(999*OneMilliSecond);
  Test(D1,D2,1);
  D2:=D1-(1001*OneMilliSecond);
  Test(D1,D2,1);
  D2:=D1-(2001*OneMilliSecond);
  Test(D1,D2,1);
  D2:=D1-(5001*OneMilliSecond);
  Test(D1,D2,5);
  D2:=D1-(5.4*OneSecond);
  Test(D1,D2,5);
  D2:=D1-(2.5*OneSecond);
  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.