浅克隆

可直接调用Object.assign()实现

深克隆

常见深克隆

//克隆函数
function deepClone(obj, newObj) {
      if (obj instanceof Array) {
            newObj = []
            return deepCloneArray(obj, newObj)
      } else if (obj instanceof Object) {
            newObj = []
            return deepCloneObject(obj, newObj)
      } else {
            return newObj = obj
      }
}
//克隆对象
function deepCloneObject(obj, newObj) {
      for (var temp in obj) {
            if (obj.hasOwnProperty(temp)) {
                  if (obj[temp] instanceof Object || obj[temp] instanceof Array) {
                        var tempNewObj = {}
                        newObj[temp] = deepClone(obj[temp], tempNewObj)
                  } else {
                        newObj[temp] = obj[temp]
                  }
            }
      }
      return newObj
}
//克隆数组
function deepCloneArray(arr, newArr) {
      for (var i = 0; i < arr.length; i++) {
            if (arr[i] instanceof Object || arr[i] instanceof Array) {
                  var tempNewArr
                  newArr[i] = deepClone(arr[i], tempNewArr)
            } else {
                  newArr[i] = arr[i]
            }
      }
      return newArr
}

便捷方法

const newObj = JSON.parse(JSON.stringify(oldObj))

• 无法实现对函数、RegExp等特殊对象的克隆
• 会抛弃对象的constructor，所有的构造函数会指向Object
• 对象有循环引用，会报错