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

# WeekSpan

Calculate the approximate number of weeks between two DateTime values.

## Declaration

Source position: dateutil.inc line 273

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

## Arguments

 ANow First moment in time AThen Second moment in time

## Function result

Number (fractions included) of weeks between ANow and AThen

## Description

WeekSpan returns the number of weeks between ANow and AThen, including any fractional parts of a week.

 YearSpan Calculate the approximate number of years between two DateTime values. MonthSpan Calculate the approximate number of months 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. MilliSecondSpan Calculate the approximate number of milliseconds between two DateTime values. WeeksBetween Calculate the number of whole weeks between two DateTime values

## Example

```Program Example57;

{ This program demonstrates the WeekSpan function }

Uses SysUtils,DateUtils;

Procedure Test(ANow,AThen : TDateTime);

begin
Write('Number of weeks between ');
Write(DateToStr(AThen),' and ',DateToStr(ANow));
Writeln(' : ',WeekSpan(ANow,AThen));
end;

Var
D1,D2 : TDateTime;

Begin
D1:=Today;
D2:=Today-7;
Test(D1,D2);
D2:=Today-8;
Test(D1,D2);
D2:=Today-14;
Test(D1,D2);
D2:=Today-35;
Test(D1,D2);
D2:=Today-36;
Test(D1,D2);
D2:=Today-17;
Test(D1,D2);
End.
```