JS 去除重复元素的方法

Array.prototype.del = function () {
    var a = {}, c = [], l = this.length;
    for (var i = 0; i < l; i++) {
        var b = this[i];
        var d = (typeof b) + b;
        if (a[d] === undefined) {
            c.push(b);
            a[d] = 1;
        }
    }
    return c;
}

var Ary = ["生活服务类", "健康保健类", "便民服务", "社区服务", "生活服务类", "健康保健类", "便民服务", "社区服务"]
Ary = Ary.del();
console.log(Ary);