CFLib.org – Common Function Library Project

Description:
Check if two dates refer to the same day. This is different from using the built-in function DateDiff("d") as it will only count whole days difference, whereas a difference of just a second could be the difference between one day and another.

Return Values:
Returns a boolean.

Example:

<cfoutput>
DifferentDay test: 
#DifferentDay("{ts '2003-01-01 23:59:59'}","{ts '2003-01-02 00:00:00'}")#<br>
Compare to DateDiff: 
#DateDiff("d","{ts '2003-01-01 23:59:59'}","{ts '2003-01-02 00:00:00'}")#
</cfoutput>

Parameters:

Full UDF Source:

/**
 * Check if two dates refer to the same day.
 * 
 * @param date1      First date to check. 
 * @param date2      Second date to check. 
 * @return Returns a boolean. 
 * @author Matthew Walker (matthew@cabbagetree.co.nz) 
 * @version 1, March 21, 2002 
 */
function DifferentDay(date1, date2) {
    return ( ( DayOfYear(date1) NEQ DayOfYear(date2) ) OR ( Year(date1) NEQ Year(date2) ) );
}