Compare 2 arrays Actionscript 3

Following is a usfull function to compare 2 arrays this is not my code i found it in an anther blog. i thought it's useful so i'm posting it here

function checkArrays(array1:Array,array2:Array):Array
{
    var array3:Array=new Array();
    var length1:int=array1.length;
    var none:Boolean=false;

    for(var i:int=0;i < length1;i++)
    {
        var length2:int=array2.length;

        for(var j:int=0;j < length2;j++)
        {
            if(String(array1[i])==String(array2[j]))
            {
                none=false;
                break;
            }
            else
            {
                none=true;
            }
        }
        if(none)
        {
            array3.push(array1[i])
            none=false;
        }
    }
    return array3;
}