CFLib.org – Common Function Library Project

Description:
Takes an Array and a Value as it arguments. Returns an array with the value appended if the value does not already exist within the array.

Return Values:
Returns a modified array or an error string.

Example:

<CFSCRIPT>
aX=ArrayNew(1);
aX[1]="a";
aX[2]="b";
aX[3]="c";
aX=ArrayAppendUnique(aX, "b"); //should do nothing
aX=ArrayAppendUnique(aX, "d"); //insert d at index 4
</CFSCRIPT> 
<CFDUMP var="#aX#">

Parameters:

Full UDF Source:

<cfscript>
/**
 * Appends a value to an array if the value does not already exist within the array.
 * 
 * @param a1 	 The array to modify. 
 * @param val 	 The value to append. 
 * @return Returns a modified array or an error string. 
 * @author Craig Fisher (&#99;&#114;&#97;&#105;&#103;&#64;&#97;&#108;&#116;&#97;&#105;&#110;&#116;&#101;&#114;&#97;&#99;&#116;&#105;&#118;&#101;&#46;&#99;&#111;&#109;) 
 * @version 1, October 29, 2001 
 */
function ArrayAppendUnique(a1,val) {
	if ((NOT IsArray(a1))) {
		writeoutput("Error in <Code>ArrayAppendUnique()</code>! Correct usage: ArrayAppendUnique(<I>Array</I>, <I>Value</I>) -- Appends <em>Value</em> to the array if <em>Value</em> does not already exist");
		return 0;
	}
	if (NOT ListFind(Arraytolist(a1), val)) {
		arrayAppend(a1, val);
	}
	return a1;
}
</cfscript>