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angular中提供了forEach()方法用于遍历对象或数组,供大家参考,具体内容如下
function forEach(obj, iterator, context) { var key, length; if (obj) {if (isFunction(obj)) { for (key in obj) {// Need to check if hasOwnProperty exists,// as on IE8 the result of querySelectorAll is an object without a hasOwnProperty functionif (key != "prototype" && key != "length" && key != "name" && (!obj.hasOwnProperty || obj.hasOwnProperty(key))) { iterator.call(context, obj[key], key, obj);} }} else if (isArray(obj) || isArrayLike(obj)) { var isPrimitive = typeof obj !== "object"; for (key = 0, length = obj.length; key < length; key++) {if (isPrimitive || key in obj) { iterator.call(context, obj[key], key, obj);} }} else if (obj.forEach && obj.forEach !== forEach) {obj.forEach(iterator, context, obj);} else if (isBlankObject(obj)) { // createMap() fast path --- Safe to avoid hasOwnProperty check because prototype chain is empty for (key in obj) {iterator.call(context, obj[key], key, obj); }} else if (typeof obj.hasOwnProperty === "function") { // Slow path for objects inheriting Object.prototype, hasOwnProperty check needed for (key in obj) {if (obj.hasOwnProperty(key)) { iterator.call(context, obj[key], key, obj);} }} else { // Slow path for objects which do not have a method `hasOwnProperty` for (key in obj) {if (hasOwnProperty.call(obj, key)) { iterator.call(context, obj[key], key, obj);} }} } return obj;}
官方描述:

forEach方法可以遍历数组或对象,函数有三个参数为别为:value,key,obj。
1)、value value指当遍历的对象或数组元素当前的值
2)、 key 是对象属性的的key或者数组的索引
3)、 obj obj即被遍历的对象或数组本身

示例:

 var values = {name: "misko", gender: "male"}; var log = []; angular.forEach(values, function(value, key) {this.push(key + ": " + value); }, log);
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。