CFLib.org – Common Function Library Project

Description:
Shuffles the values in a one-dimensional array. This functions takes a one-dimensional array and returns a new one with the values from the first randomly shuffled.

Return Values:
Returns an array.

Example:

<cfset a=arrayNew(1)>
<cfloop index="i" from="1" to="10">
    <cfset a[i]=i>
</cfloop>
<cfset a1=ArrayShuffle(a)><br><br>

<CFLOOP FROM="1" TO="#ArrayLen(a1)#" INDEX="i">
<CFOUTPUT>
#a1[i]#<BR>
</CFOUTPUT>
</CFLOOP>

Parameters:

Full UDF Source:

/**
 * Shuffles the values in a one-dimensional array.
 * 
 * @param ar      One dimensional array you want shuffled. 
 * @return Returns an array. 
 * @author Ivan Latunov (ivan@cfchat.net) 
 * @version 1, October 9, 2001 
 */
function ArrayShuffle(ar) {
    var ar1=ArrayNew(1);
    var i=1;
    var n=1;
    var len=ArrayLen(ar);
    if (NOT IsArray(ar,1)) {
        writeoutput("Error in <Code>ArrayShuffle()</code>! Correct usage: ArrayShuffle(<I>Array</I>) - Shuffles the values in one dimensional Array");
        return 0;
    }
    
    if (ArrayLen(ar) eq 0) {
        return ar1;
    }
    
    for (i=1; i lte len; i=i+1) {
        n = RandRange(1,ArrayLen(ar));
        ArrayAppend(ar1,ar[n]);
        ArrayDeleteAt(ar,n);
    }
    return ar1;
}