CFLib.org – Common Function Library Project

Description:
This function is similar to optArg() except that it allows you to specify a type of the argument, if the provided arg isn't the correct type, then the default value is used. Also when types "structure" and "array" are used an empty array / struct is created when no default value is specified. This tag requires the typeOf() udf to work.

Return Values:
Returns a value (any type).

Example:

<cfscript>
function foo( p1 ) {
    var s = structNew();
    var p2 = optArgType( arguments, 2, "structure" );
    var p3 = optArgType( arguments, 3, "array", listToArray( "foo,bar,grill" ));

    s.p2 = p2;
    s.p3 = p3;
    return s;
}
</cfscript>
<cfdump var="#foo(1)#">

Parameters:

Full UDF Source:

/**
 * Pass in an optional UDF argument of a specific type and define a default value at once.
 * 
 * @param args      Arguments to check. (Required)
 * @param index      Index to check. (Required)
 * @param type      Type to use. (Required)
 * @param default      Value to use if args[index] doesn't exist. Defaults to an empty string if type isn't struct or array. (Optional)
 * @return Returns a value (any type). 
 * @author Jordan Clark (JordanClark@Telus.net) 
 * @version 1, August 20, 2002 
 */
function OptArgType( args, index, type ) {
    if( arrayLen( args ) GTE index AND typeOf( args[ index ] ) IS type ) {
        return args[ index ];
    } else if( arrayLen( arguments ) IS 4 ) {
        return arguments[ 4 ];
    } else {
        switch( type ) {
            case "structure" : return structNew();
            case "array" : return arrayNew( 1 );
            default : return "";
        }
    }
}