js-数组的原型拓展

Array.prototype.contain = function(e){
    for(i=0;i<this.length;i++){
        if(this[i] == e)
        return true;
    }
    return false;
};

Array.prototype.indexOf = function(val) {
    for (var i = 0; i < this.length; i++) {
        if (this[i] == val) return i;
    }
    return -1;
};
Array.prototype.remove = function(val) {
    var index = this.indexOf(val);
    if (index > -1) {
        this.splice(index, 1);
    }
};

Array.prototype.distinct=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;
};