function ray console col ole fun log else style
forEach函数遍历数组:
- var arr = [1, 2, 3];
- arr.forEach(function(item, index) {
- console.log(index, item)
- })
forEach函数遍历对象:
- var obj = {
- x: 100,
- y: 200,
- z: 300
- }
- var key;
- for (key in obj) {
- if (obj.hasOwnProperty(key)) {
- console.log(key, obj[key])
- }
- }
能遍历二者的forEach函数
- function forEach(obj, fn) {
- var key;
- if (obj instanceof Array) {
- obj.forEach(function(item, index) {
- fn(item, index)
- })
- } else {
- for (key in obj) {
- if (obj.hasOwnProperty(key)) {
- fn(key, obj[key])
- }
- }
- }
- }
- var arr = [1, 2, 3];
- var obj = {
- x: 100,
- y: 200,
- z: 300
- }
- forEach(arr,
- function(item, index) {
- console.log(index, item)
- }) forEach(obj,
- function(key, val) {
- console.log(key, val)
- })
写一个能遍历数组和对象的forEach函数
function ray console col ole fun log else style
原文:http://www.cnblogs.com/yoyoy/p/8007449.html
来源: http://www.bubuko.com/infodetail-2421860.html