CFLib.org – Common Function Library Project

Description:
Returns the "am/pm" portion of a time/date (aka the "meridiem"). Works with both dates created via plain text (i.e. "4/1/2012") and via CreateDateTime(), etc. This is basically a wrapper around the call to TimeFormat() to both a) add some extra validation for dealing with potentially badly formatted dates and b) uses the proper "meridiem" name for this portion of the timestamp, adding some readability to the code.

Return Values:
Returns a string that is either AM or PM

Example:

// example with date/times showing the cut-over from AM to PM
baseTS = createDateTime(year(now()), month(now()), day(now()), 11, 59, 55);
for (i=0; i <= 10; i++){
    testTs = dateAdd("s", i, baseTs);
    writeOutput("#testTs#: #getMeridiem(testTs)#<br />");
}

Parameters:

Full UDF Source:

/**
 * I return the "am/pm" portion of a date/time (aka the "meridiem").
 * * version 0.1 by Nolan Erck
 * * version 0.2 by Nolan Erck: fixing small bug
 * * version 1.0 by Adam Cameron: factoring-out redundant date-checking logic
 * 
 * @param dateTime      A datetime as a date or a string that will parse as a datetime (Required)
 * @return Returns a string that is either AM or PM 
 * @author Nolan Erck (nolan@southofshasta.com) 
 * @version 1.1, November 14, 2012 
 */
string function getMeridiem(required date dateTime){
    return timeFormat(dateTime, "tt");
}