Functions Delphi

function IncDay ( const StartDateTime : TDateTime {; NumberOfDays : Integer = 1} ) : TDateTime;


Description
The IncDay function returns a TDateTime value that is NumberOfDays greater than the passed StartDateTime value.

The year and month values are incremented as appropriate.

The increment value is optional, being 1 by default.

Notes
There is no DecDay function.
Instead, use IncDay with a negative increment.


Related commands
IncMinute Increments a TDateTime variable by + or - number of minutes
IncMonth Increments a TDateTime variable by a number of months
IncYear Increments a TDateTime variable by a number of years
IncSecond Increments a TDateTime variable by + or - number of seconds
IncMillisecond Increments a TDateTime variable by + or - number of milliseconds

Example code : A simple example of increment and decrement
var
myDate : TDateTime;
begin
// Set up our date just before the end of the year 2000
myDate := EncodeDate(2000, 12, 30);
ShowMessage('myDate = '+DateToStr(myDate));
// Add 10 days to this date
myDate := IncDay(myDate, 10);
ShowMessage('myDate + 10 days = '+DateToStr(myDate));
// Subtract 12 days from this date
myDate := IncDay(myDate, -12);
ShowMessage('myDate - 12 days = '+DateToStr(myDate));
end;

Show full unit code
myDate = 30/12/2000
myDate + 10 days = 09/01/2001
myDate - 12 days = 29/12/2000