废话不多说了，直接给大家上array对象扩展代码了，具体代码如下所示：
调用给定的函数，然后把得到的结果放到新数组中返回
if (typeof Array.prototype.map != "function") {
Array.prototype.map = function (fn,context) {
var arr = [];
if (typeof fn === "function") {
for (var k = 0,length = this.length; k < length; k++) {
arr.push(fn.call(context,this[k],k,this));
}
}
return arr;
};
}
// 把符合条件的元素放到一个新数组中返回
if (typeof Array.prototype.filter != "function") {
Array.prototype.filter = function (fn,length = this.length; k < length; k++) {
fn.call(context,this) && arr.push(this[k]);
}
}
return arr;
};
}
// 如果数组中的每个元素都能通过给定的函数的测试，则返回true，反之false
if (typeof Array.prototype.every != "function") {
Array.prototype.every = function (fn,context) {
var passed = true;
if (typeof fn === "function") {
for (var k = 0,length = this.length; k < length; k++) {
if (passed === false) break;
passed = !!fn.call(context,this);
}
}
return passed;
};
}
// 类似every函数，但只要有一个通过给定函数的测试就返回true
if (typeof Array.prototype.some != "function") {
Array.prototype.some = function (fn,context) {
var passed = false;
if (typeof fn === "function") {
for (var k = 0,length = this.length; k < length; k++) {
if (passed === true) break;
passed = !!fn.call(context,this);
}
}
return passed;
};
}
// 返回元素在数组的索引，没有则返回-1，从左到右
if (typeof Array.prototype.indexOf != "function") {
Array.prototype.indexOf = function (item,index) {
var n = this.length,i = index == null ? 0 : index < 0 ? Math.max(0,n + index) : index;
for (; i < n; i++) {
if (i in this && this[i] === item) {
return i
}
}
return -1
};
}
// 返回元素在数组的索引，没有则返回-1，从右到左
if (typeof Array.prototype.lastIndexOf != "function") {
Array.prototype.lastIndexOf = function (item,i = index == null ? n-1 : index < 0 ? Math.max(0,n + index) : index;
for (; i >= 0; i--) {
if (i in this && this[i] === item) {
return i;
}
}
return -1;
};
}
// 让数组元素依次调用给定函数，最后返回一个值（从左到右）
if (typeof Array.prototype.reduce != "function") {
Array.prototype.reduce = function (callback,initialValue) {
var prevIoUs = initialValue,k = 0,length = this.length;
if (typeof initialValue === "undefined") {
prevIoUs = this[0];
k = 1;
}
if (typeof callback === "function") {
for (k; k < length; k++) {
this.hasOwnProperty(k) && (previous = callback(previous,this));
}
}
return previous;
};
}
// 让数组元素依次调用给定函数，最后返回一个值（从右到左）
if (typeof Array.prototype.reduceRight != "function") {
Array.prototype.reduceRight = function (callback,initialValue) {
var length = this.length,k = length - 1,previous = initialValue;
if (typeof initialValue === "undefined") {
previous = this[length - 1];
k--;
}
if (typeof callback === "function") {
for (k; k > -1; k-=1) {
this.hasOwnProperty(k) && (prevIoUs = callback(prevIoUs,this));
}
}
return prevIoUs;
};
}
// 去掉重复项（唯一性），返回新数组
if (typeof Array.prototype.uniq != "function") {
Array.prototype.uniq = function() {
var arr = [];
arr[0] = this[0];
for (var i = 1; i < this.length; i++) {
if (arr.indexOf(this[i]) == -1) {
arr.push(this[i]);
}
}
return arr;
};
}
// 指定删除数组中某值
if (typeof Array.prototype.remove != "function") {
Array.prototype.remove = function(item) {
for (var i = this.length; i >= 0; i--) {
if (item === this[i]) {
this.splice(i,1);
}
}
return this;
};
}
// 打乱数组顺序
if (typeof Array.prototype.shuffle != "function") {
Array.prototype.shuffle = function() {
var i = this.length;
while (i) {
var j = Math.floor(Math.random()*i);
var t = this[--i];
this[i] = this[j];
this[j] = t;
}
return this;
};
}
// 求数组的最大值
if (typeof Array.prototype.max != "function") {
Array.prototype.max = function() {
return Math.max.apply({},this)
};
}
// 求数组的最小值
if (typeof Array.prototype.max != "function") {
Array.prototype.min = function() {
return Math.min.apply({},this)
};
}
// 判断是否为数组
if (typeof Array.prototype.isArray != "function") {
Array.prototype.isArray = function() {
return Object.prototype.toString.apply(this) === "[object Array]";
};
}
}());
