前端深拷贝非常优质的函数，包含函数、循环引用，Set、Map、Date、自定义构造函数等处理

前端深拷贝

function deepClone(obj: any, hash = new WeakMap()): any {if (Object(obj) !== obj) return obj // 处理基础类型if (hash.has(obj)) return hash.get(obj) // 处理循环引用const result = Array.isArray(obj)? []: obj instanceof Set? new Set(obj): obj instanceof Map? new Map(Array.from(obj, ([key, val]) => [key, deepClone(val, hash)])): obj instanceof Date? new Date(obj.getTime()): obj instanceof RegExp? new RegExp(obj.source, obj.flags): typeof obj === 'function'? obj: obj.constructor? new obj.constructor(): Object.create(null)hash.set(obj, result)return Object.assign(result, ...Object.keys(obj).map((key) => ({ [key]: deepClone(obj[key], hash) })))}

单元测试

it('深拷贝测试', () => {function deepClone(obj: any, hash = new WeakMap()): any {if (Object(obj) !== obj) return obj // 处理基础类型if (hash.has(obj)) return hash.get(obj) // 处理循环引用const result = Array.isArray(obj)? []: obj instanceof Set? new Set(obj): obj instanceof Map? new Map(Array.from(obj, ([key, val]) => [key, deepClone(val, hash)])): obj instanceof Date? new Date(obj.getTime()): obj instanceof RegExp? new RegExp(obj.source, obj.flags): typeof obj === 'function'? obj: obj.constructor? new obj.constructor(): Object.create(null)hash.set(obj, result)return Object.assign(result, ...Object.keys(obj).map((key) => ({ [key]: deepClone(obj[key], hash) })))}const obj = {date: new Date(1716433194530),regex: /test/i,map: new Map([['key', { nested: 'value' }]]),set: new Set([1, 2, 3]),func: function () {console.log('Hello!')},nested: { a: 1, b: [2, 3] },n: null,un: undefined}const clone = deepClone(obj)expect(clone).toEqual(obj)expect(clone).not.toBe(obj)expect(clone.nested).not.toBe(obj.nested)expect(clone.map.get('key')).not.toBe(obj.map.get('key'))expect(clone.date.getTime()).toBe(obj.date.getTime())expect(clone.regex.source).toBe(obj.regex.source)expect(clone.regex.flags).toBe(obj.regex.flags)expect(Array.from(clone.set)).toEqual(Array.from(obj.set))expect(clone.func.toString()).toBe(obj.func.toString())expect(clone.n).toBe(obj.n)expect(clone.un).toBe(obj.un)})