Question

我有两个数组，名称分别为changeemployeesarray和allemployees。

var changedemployeesarray = [
  {
    "empId": "1126",
    "name": "sam"
  },
  {
    "empId": "1128",
    "name": "mike"
  },
  {
    "empId": "1134",
    "name": "steve"
  }
]


var allemployees = [
  {
    "empFullName": "sam Raj",
    "empInfo": {
      "empSeq": "1126",
      "createDate": "2018-10-17"
    },
    "modfiedDate": "2018-10-24"
  },
  {
    "empFullName": "mike",
    "empInfo": {
      "empSeq": "1128",
      "createDate": "2018-10-17"
    },
    "modfiedDate": "2018-10-24"
  },
  {
    "empFullName": "steve",
    "empInfo": {
      "empSeq": "1134",
      "createDate": "2018-10-17"
    },
    "modfiedDate": "2018-10-24"
  }
]

如果allemployees数组中存在/找到了changeemployeesarray的empId，我想插入到updatearray中。如果找不到，将其插入createarray

我已经遵循了这种方法，有没有更好的方法

https://jsfiddle.net/o2gxgz9r/74296/

预期输出

updatearray

[{"empId":"1126","name":"sam"},{"empId":"1128","name":"mike"}]

createarray

[{"empId":"1136","name":"steve"}]

Answer 1

您可以使用filter来获得2个数组。

knock

Answer 2

您可以尝试关注。它解决了线性复杂度问题。

从changedemployeesarray
现在遍历allemployees并在匹配项上填充updatearray，并从上面创建的对象中删除条目
obj中所有其余条目均丢失，即created。以此填充createarray。

var changedemployeesarray = [{"empId":"1126","name":"sam"},{"empId":"1128","name":"mike"},{"empId":"1136","name":"steve"}];
var allemployees = [{"empFullName":"sam Raj","empInfo":{"empSeq":"1126","createDate":"2018-10-17"},"modfiedDate":"2018-10-24"},{"empFullName":"mike","empInfo":{"empSeq":"1128","createDate":"2018-10-17"},"modfiedDate":"2018-10-24"},{"empFullName":"steve","empInfo":{"empSeq":"1134","createDate":"2018-10-17"},"modfiedDate":"2018-10-24"}];

// Step 1 - Create object from changedemployeesarray
let obj = changedemployeesarray.reduce((a,c) => Object.assign(a, {[c.empId] : c}), {});

// Step 2 - Populate updatearray in case of match
let updatearray = allemployees.reduce((a,c) => {
  if(obj[c.empInfo.empSeq]) {
    a.push(obj[c.empInfo.empSeq]);
    delete obj[c.empInfo.empSeq];
  }
  return a;
}, []);
// Step 3 - Populate createarray with remaining values (missing means created)
let createarray = Object.values(obj);
console.log(createarray);
console.log(updatearray);

Answer 3

由于您将UNIQUE键设置为“ empid”，因此最佳实践是创建单个数组并在后端使用“ ON DUPLICATE KEY UPDATE”。如果empid已经存在，它将更新条目。

如何比较两个数组并将其插入更新或创建数组

3 个答案: