JS 通过递归 实现对象深拷贝

const deepClone = (obj) => {
  var target
  if (obj === null || typeof obj !== 'object') return obj

  if (obj instanceof Array) {
    target = []
    obj.forEach((item) => {
      target.push(deepClone(item))
    })
    return target
  }

  if (obj instanceof Object) {
    target = {}
    let objKeys = Object.keys(obj)
    objKeys.forEach((key) => {
      target[key] = deepClone(obj[key])
    })
    return target
  }
}