Javascript String hexEncode8()

String.prototype.hexEncode8 = function(){
    var hex, i;//from  www.  j a v  a2 s.c  om
    var result = "";
    for (i=0; i<this.length; i++) {
        hex = this.charCodeAt(i).toString(16);
        result += ("0"+hex).slice(-2);
    }
    return result
}