js深拷贝 和封装的js排序方法sort（前端网备份）

先来说浅拷贝
var arr = ["a","b"];
var arrCopy = arr;
arrCopy[1] = "c";
arr // => ["a","c"]

然后再来说一下简易版深拷贝封装
function clone(obj) {
var c = {};
c = JSON.parse(JSON.stringify(obj));
return c;
}
至于序列化为何会深拷贝，参考
https://www.imooc.com/article/70653

// arr是需要传的对象数组；obj
// field是需要排序对象数组的字段;string
// sort: string
function sort(arr,field,sort) {
if(sort==null || sort==''){
sort="asc";
}
var len = arr.length;
for (var i = 0; i < len; i++) {
for (var j = 0; j < len - 1 - i; j++) {
if(sort=="desc"){
if (arr[j][field] < arr[j + 1][field]) {
var temp = arr[j + 1];
arr[j + 1] = arr[j];
arr[j] = temp;
}
}else{
if (arr[j][field] > arr[j + 1][field]) {
var temp = arr[j + 1];
arr[j + 1] = arr[j];
arr[j] = temp;
}
}
}
}
return arr;
}

复杂对象深拷贝

//深拷贝
    copyFn(obj) {
      if (obj == null) {
        return null;
      }
      var result = Array.isArray(obj) ? [] : {};
      for (let key in obj) {
        if (obj.hasOwnProperty(key)) {
          if (typeof obj[key] === 'object') {
            result[key] = this.copyFn(obj[key]); // 如果是对象，再次调用该方法自身
          } else {
            result[key] = obj[key];
          }
        }
      }
      return result;
    },

案例为

form: {
        // projectId: '',
        // id: '',
        manufacturerName: '',
        manufacturerDescribe: '',
        thirdPartyContactList: [
          {
            id: '',
            contactor: '',
            contactPhone: '',
            contactJobTitle: ''
          }
        ]
      },

Object.assign这种拷贝只能拷贝一层,form.thirdPartyContactList就无法拷贝了