fenzhi-utils/globalMethods/CustomObject/CustomDeepClone.js

分值前端项目的js函数库

/**
 * 深度克隆函数(包含函数、原型链、数组、循环引用，Symbol、Map、Set等)
 * @param {*} obj
 * @param {*} [hash=new WeakMap()]
 * @return {*}
 */

/**
// 测试一：
let obj = {
  str: 'hello world',
  num: 123,
  bool: true,
  nul: null,
  und: undefined,
  arr: [1, 2, 3],
  obj: { a: 1, b: 2, c: 3 },
  func: function () {
    console.log('hello world');
  },
  sym: Symbol('hello'),
  map: new Map([
    ['name', 'Tom'],
    ['age', 18],
  ]),
  set: new Set([1, 2, 3]),
};
obj.loop = obj; // 循环引用
let cloneObj = CustomDeepClone(obj);
console.log(cloneObj);
obj.str = 'AIGC';
console.log(cloneObj);
cloneObj.str = 'WEBAI';
console.log(cloneObj);
console.log(obj);

// 测试二：
let arr1 = [{ a: 6 }, { a: 7 }];
let arr2 = CustomDeepClone(arr1);
arr1[0].a = 8;
arr2[0].a = 9;
console.log(arr1);// [{ a: 8 }, { a: 7 }]
console.log(arr2);// [{ a: 9 }, { a: 7 }]
 */
export function CustomDeepClone(obj, hash = new WeakMap()) {
  if (
    Object(obj) !== obj ||
    obj instanceof Function ||
    obj instanceof RegExp ||
    obj instanceof Error ||
    obj instanceof Date
  ) {
    return obj;
  }

  if (hash.has(obj)) {
    return hash.get(obj);
  }

  let result;
  try {
    result = new obj.constructor();
  } catch (e) {
    result = Object.create(Object.getPrototypeOf(obj));
  }

  hash.set(obj, result);

  if (obj instanceof Map) {
    Array.from(obj, ([key, val]) =>
      result.set(deepClone(key, hash), deepClone(val, hash))
    );
  } else if (obj instanceof Set) {
    Array.from(obj, (key) => result.add(deepClone(key, hash)));
  } else if (Array.isArray(obj)) {
    result = obj.map((item) => deepClone(item, hash));
  } else {
    result = Object.getOwnPropertyNames(obj).reduce((acc, key) => {
      const descriptor = Object.getOwnPropertyDescriptor(obj, key);
      if (
        descriptor.value !== undefined &&
        typeof descriptor.value !== 'function'
      ) {
        descriptor.value = deepClone(descriptor.value, hash);
      } else if (descriptor.get || descriptor.set) {
        descriptor.get = deepClone(descriptor.get, hash);
        descriptor.set = deepClone(descriptor.set, hash);
      }
      Object.defineProperty(acc, key, descriptor);
      return acc;
    }, result);
    Object.setPrototypeOf(result, deepClone(Object.getPrototypeOf(obj), hash));
  }

  if (obj instanceof Map) {
    Object.setPrototypeOf(result, Map.prototype);
  } else if (obj instanceof Set) {
    Object.setPrototypeOf(result, Set.prototype);
  }

  return result;
}