javascript函数原型

// 去除字符串两边的空格String.prototype.trim = function() {    var re = /(^\s*)|(\s*)$/g;    return this.replace(re, "");}// 删除数组中某个元素Array.prototype.remove = function(i) {    var o = this[i];    for (var j = i; j < this.length - 1; j ++) {        this[j] = this[j + 1]; //从第i个元素开始，到倒数第二个元素，用后面的元素替代前面的元素    }    -- this.length;     return o;}// 判断一个数组中是否存在相同的元素Array.prototype.search = function(o) {    for (var i = 0; i < this.length; i ++) {        if (this[i] == o) {            return i;        }    }    return -1;}//下面是测试var str = " This is test string   ";console.log(str);console.log(str.trim());console.log(str);var arr = [1, 2, 3, 4];console.log(arr.length);console.log(arr.remove(2));console.log(arr);var arr = [1, 2, 3, 4];console.log(arr.search(5));console.log(arr.search(3));

参考：http://security.ctocio.com.cn/tips/337/7716837_3.shtml