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

# WeekSpan

Calculate the approximate number of weeks between two TDateTime values.

## Declaration

Source position: dateutil.inc line 286

 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 TDateTime values. MonthSpan Calculate the approximate number of months 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. MilliSecondSpan Calculate the approximate number of milliseconds between two TDateTime values. WeeksBetween Calculate the number of whole weeks between two TDateTime 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.
```