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

# MilliSecondSpan

Calculate the approximate number of milliseconds between two TDateTime values.

## Declaration

Source position: dateutil.inc line 291

 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.

## See also

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