map
特点:
map处理return出来的值，把值放在一个新的数组，默认返回undefined。
浅拷贝，会改变原数组。
浅度map实现
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| Array.prototype.myMap = function(func) {
var len = this.length,
newArr = [];
for(var i = 0; i < len; i++) {
newArr.push(func(this[i], i));
}
return newArr;
}
|
深度map实现
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| // 深度克隆
function deepClone(target, option) {
if(option !== null) {
for(var prop in option) {
var src = target[prop],
copy = option[prop];
if(typeof(copy) === 'object') {
if(Object.prototype.toString(copy) === '[object Array]') {
src = [];
}else {
src = {};
}
target[prop] = deepClone(src, copy);
}else {
target[prop] = copy;
}
}
}
return target;
}
Array.prototype.myMap = function(func) {
var len = this.length,
newArr = [];
for(var i = 0; i < len; i++) {
if(this[i] && Object.prototype.toString.call(this[i]) === '[object Object]') {
var newObj = {};
deepClone(newObj, this[i]);
newArr.push(func(newObj, i));
}else if(this[i] && Object.prototype.toString.call(this[i]) === '[object Array]') {
var Arr = [];
deepClone(newArr, this[i]);
newArr.push(func(Arr, i));
}else {
newArr.push(func(this[i], i));
}
}
return newArr;
}
|
