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WithinPastMilliSeconds

Check whether two TDateTimes are only a number of milliseconds apart

Declaration

Source position: dateutil.inc line 250

  function WithinPastMilliSeconds(const ANow: TDateTime; 
                                 const AThen: TDateTime; 
                                 const AMilliSeconds: Int64) : Boolean;

Description

WithinPastMilliSeconds compares the timestamps ANow and AThen and returns True if the difference between them is at most AMilliSeconds milliseconds apart, or False if they are further apart.

Remark

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

See also

Name Description
WithinPastDays Check whether two TDateTimes are only a number of days apart
WithinPastHours Check whether two TDateTimes are only a number of hours apart
WithinPastMinutes Check whether two TDateTimes are only a number of minutes apart
WithinPastMonths Check whether two TDateTimes are only a number of months apart
WithinPastSeconds Check whether two TDateTimes are only a number of seconds apart
WithinPastWeeks Check whether two TDateTimes are only a number of weeks apart
WithinPastYears Check whether two TDateTimes are only a number of years apart

Example

Program Example54;
{ This program demonstrates the WithinPastMilliSeconds function }
Uses SysUtils,DateUtils;
Procedure Test(ANow,AThen : TDateTime; AMilliSeconds : Integer);
begin
 Write(TimeToStr(AThen),' and ',TimeToStr(ANow));
 Write(' are within ',AMilliSeconds,' milliseconds: ');
 Writeln(WithinPastMilliSeconds(ANow,AThen,AMilliSeconds));
end;
Var
  D1,D2 : TDateTime;
Begin
  D1:=Now;
  D2:=D1-(0.9*OneMilliSecond);
  Test(D1,D2,1);
  D2:=D1-(1.0*OneMilliSecond);
  Test(D1,D2,1);
  D2:=D1-(1.1*OneMilliSecond);
  Test(D1,D2,1);
  D2:=D1-(2.5*OneMilliSecond);
  Test(D1,D2,1);
  Test(D1,D2,2);
  Test(D1,D2,3);
End.