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@@ -0,0 +1,161 @@
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+/**
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+ * 模拟构造函数创建对象
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+ * @param {*} Fn
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+ * @param {...any} args
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+ * @returns
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+ */
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+function newInstance(Fn,...args){
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+ const obj = {}
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+ const result = Fn.call(obj,...args)
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+ obj.__proto__ = Fn.prototype
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+ return result instanceof Object ? result : obj
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+}
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+/**
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+ * 判断
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+ * @param {*} obj
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+ * @param {*} Fn
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+ * @returns
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+ */
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+function myInstanceOf(obj,Fn){
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+ let prototype = Fn.prototype
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+ let proto = obj.__proto__
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+ while(proto){
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+ if(proto === prototype){
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+ return true
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+ }
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+ proto = proto.__proto__
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+ }
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+ return false
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+}
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+/**
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+ * 合并数组
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+ * @param {...any} objs
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+ * @returns
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+ */
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+function mergeObject(...objs){
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+ const result = {}
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+ objs.forEach(obj =>{
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+ //获取所有属性
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+ Object.keys(obj).forEach(key=>{
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+ //检测result是否存在key
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+ if(result.hasOwnProperty(key)){
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+ result[key] = [].concat(result[key],obj[key])
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+ }else{
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+ result[key] = obj[key]
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+ }
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+ })
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+ })
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+ return result
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+}
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+/**
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+ * 浅拷贝1
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+ * @param {*} target
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+ * @returns
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+ */
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+function clone1(target){
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+ if(typeof target === 'object' && target !== null){
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+ if(Array.isArray(target)){
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+ return [...target]
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+ }else{
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+ return {...target}
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+ }
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+ }
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+ return target
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+}
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+/**
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+ * 浅拷贝2
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+ * @param {*} target
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+ * @returns
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+ */
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+ function clone2(target){
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+ if(typeof target === 'object' && target !== null){
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+ //创建容器
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+ const result = Array.isArray(target)?[]:{}
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+ for(let key in target){
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+ //判断当前对象是否包含该属性
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+ if(target.hasOwnProperty(key)){
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+ result[key] = target[key]
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+ }
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+ }
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+ return result
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+ }
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+ return target
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+}
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+
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+/**
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+ * 深拷贝1 缺点：不能克隆方法、不能循环引用
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+ * @param {*} target
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+ * @returns
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+ */
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+function deepClone1(target){
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+ return JSON.parse(JSON.stringify(target))
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+}
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+/**
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+ * 深拷贝2 未能解决循环引用
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+ * @param {*} target
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+ * @returns
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+ */
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+function deepClone2(target){
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+ if(typeof target === 'object' && target !== null){
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+ const result = Array.isArray(target)?[]:{}
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+ for(let key in target){
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+ if(target.hasOwnProperty(key)){ //此处可枚举，防止原型属性被拷贝
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+ result[key] = deepClone2(target[key])
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+ }
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+ }
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+ return result
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+ }else{
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+ return target
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+ }
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+}
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+
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+/**
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+ * 深拷贝3 解决循环引用
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+ * @param {*} target
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+ * @param {*} map
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+ * @returns
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+ */
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+ function deepClone2(target,map = new Map()){
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+ if(typeof target === 'object' && target !== null){
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+ let cache = map.get(target)
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+ if(cache) return cache
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+ const result = Array.isArray(target)?[]:{}
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+ map.set(target,result)
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+ for(let key in target){
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+ if(target.hasOwnProperty(key)){ //此处可枚举，防止原型属性被拷贝
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+ result[key] = deepClone3(target[key],map)
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+ }
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+ }
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+ return result
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+ }else{
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+ return target
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+ }
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+}
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+
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+/**
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+ * 深拷贝4 性能优化 for in效率较低，使用foreach和object.keys
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+ * @param {*} target
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+ * @param {*} map
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+ * @returns
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+ */
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+ function deepClone2(target,map = new Map()){
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+ if(typeof target === 'object' && target !== null){
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+ let cache = map.get(target)
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+ if(cache) return cache
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+ let isArray = Array.isArray(target)
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+ const result = isArray?[]:{}
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+ map.set(target,result)
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+ if(isArray){
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+ target.forEach((item,index)=>{
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+ result[index] = deepClone4(item,map)
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+ })
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+ }else{
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+ Object.keys(result).forEach(key =>{
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+ result[key] = deepClone4(target[key],map)
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+ })
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+ }
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+ return result
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+ }else{
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+ return target
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+ }
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+}
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