JavaScript: Chuyển tiếng Việt có dấu sang không dấu

ConvertVie.js

function change_alias(alias) {
    var str = alias;
    str = str.toLowerCase();
    str = str.replace(/à|á|ạ|ả|ã|â|ầ|ấ|ậ|ẩ|ẫ|ă|ằ|ắ|ặ|ẳ|ẵ/g,"a"); 
    str = str.replace(/è|é|ẹ|ẻ|ẽ|ê|ề|ế|ệ|ể|ễ/g,"e"); 
    str = str.replace(/ì|í|ị|ỉ|ĩ/g,"i"); 
    str = str.replace(/ò|ó|ọ|ỏ|õ|ô|ồ|ố|ộ|ổ|ỗ|ơ|ờ|ớ|ợ|ở|ỡ/g,"o"); 
    str = str.replace(/ù|ú|ụ|ủ|ũ|ư|ừ|ứ|ự|ử|ữ/g,"u"); 
    str = str.replace(/ỳ|ý|ỵ|ỷ|ỹ/g,"y"); 
    str = str.replace(/đ/g,"d");
    str = str.replace(/!|@|%|\^|\*|\(|\)|\+|\=|\<|\>|\?|\/|,|\.|\:|\;|\'|\"|\&|\#|\[|\]|~|\$|_|`|-|{|}|\||\\/g," ");
    str = str.replace(/ + /g," ");
    str = str.trim(); 
    return str;
}