[Overview][Constants][Procedures and functions][Index] Reference for unit 'dateutils' (#rtl)

# MilliSecondSpan

Calculate the approximate number of milliseconds between two DateTime values.

## Declaration

Source position: dateutil.inc line 277

 function MilliSecondSpan( const ANow: TDateTime; const AThen: TDateTime ):Double;

## Arguments

 ANow First moment in time AThen Second moment in time

## Function result

Number (fractions included) of seconds between ANow and AThen

## Description

MilliSecondSpan returns the number of milliseconds between ANow and AThen. Since millisecond is the smallest fraction of a TDateTime indication, the returned number will always be an integer value.

 YearSpan Calculate the approximate number of years between two DateTime values. MonthSpan Calculate the approximate number of months between two DateTime values. WeekSpan Calculate the approximate number of weeks between two DateTime values. DaySpan Calculate the approximate number of days between two DateTime values. HourSpan Calculate the approximate number of hours between two DateTime values. MinuteSpan Calculate the approximate number of minutes between two DateTime values. SecondSpan Calculate the approximate number of seconds between two DateTime values. MilliSecondsBetween Calculate the number of whole milliseconds between two DateTime values.

## Example

```Program Example70;

{ This program demonstrates the MilliSecondSpan function }

Uses SysUtils,DateUtils;

Procedure Test(ANow,AThen : TDateTime);

begin
Write('Number of milliseconds between ');
Write(TimeToStr(AThen),' and ',TimeToStr(ANow));
Writeln(' : ',MilliSecondSpan(ANow,AThen));
end;

Var
D1,D2 : TDateTime;

Begin
D1:=Now;
D2:=D1-(0.9*OneMilliSecond);
Test(D1,D2);
D2:=D1-(1.0*OneMilliSecond);
Test(D1,D2);
D2:=D1-(1.1*OneMilliSecond);
Test(D1,D2);
D2:=D1-(2.5*OneMilliSecond);
Test(D1,D2);
End.
```