Array.prototype.contains = function(obj) {    var i = this.length;    while (i--) {        if (this[i] === obj) {            return true;        }    }    return false;}或Array.prototype.contains = function(element) {    for (var i = 0; i < this.length; i++) {        if (this[i] == element) {            return true;        }    }    return false;}或Array.prototype.in_array = function(e) {    for(i=0; i