javascript 数组去重

//去除数字元素数组
function sortnum(a, b) {
        return a - b;
}
Array.prototype.unique1 = function() {
        this.sort(sortnum);
        var newnumbers = [this[0]];
        for (var i = 0; i < this.length; i++) {
                if (this[i] != newnumbers[newnumbers.length - 1]) {
                        newnumbers.push(this[i]);
                }
        };
        return newnumbers;
};
var mynums = [1, 2, 5, 8, 2, 5, 7, 42, 8, 0];
mynums = mynums.unique1();
console.log(mynums);

//利用json对象 能够取出非数字元素
Array.prototype.jsonUnique = function() {
        var json = {};
        for (var i = 0; i < this.length; i++) {
                if(!json[this[i]]){
                        json[this[i]] = 1;
                }
        };
        return json;
};

var mynumss = [1,2,54,1,43,54,'哈哈','哈哈','我们','为什么','为什么'];
mynumss = mynumss.jsonUnique();
for(var key in mynumss){
        console.log(key);
}