How to push objects that are inside array of objects into another array?-CodePudding

I have a part of code that looks like this where I need to pick objects out of array of objects and push them into an array.

    var issues = await Issues.find({})
    console.log(issues)
    let issuesData = [];
    for (issue of issues) {
            console.log(issue)
            issuesData.push(issue['data'])
    }

The output of issues is

[
  {
    _id: new ObjectId("6346e32032eae0a8d1986bf0"),
    data: { no: 1, date: '31-10-2022', cover: 'path/to/cover/image' },
    articles: [ [Object], [Object] ],
    letters: [ [Object], [Object] ]
  },
  {
    _id: new ObjectId("6346e37c32eae0a8d198a3bf"),
    data: { no: 2, date: '31-12-2022', cover: 'path/to/cover/image' },
    articles: [ [Object], [Object] ],
    letters: [ [Object], [Object] ]
  }
]

and in issuesData I want an array like

[ { no: 1, date: '31-10-2022', cover: 'path/to/cover/image' }, { no: 2, date: '31-12-2022', cover: 'path/to/cover/image' } ]

but I get an undefined when I push issue['data']

CodePudding user response：

I tried and it seems working fine for me. However a better way is to remove the for loop and replace it with let issuesData = issues.map(issue => issue.data) to get the same expected output.

CodePudding user response：

You can simply apply the map function which will take care of your problem.
Try this:

const data = [
      {
        _id: "6346e32032eae0a8d1986bf0",
        data: { no: 1, date: '31-10-2022', cover: 'path/to/cover/image' },
        articles: [],
        letters: []
      },
      {
        _id: "6346e37c32eae0a8d198a3bf",
        data: { no: 2, date: '31-12-2022', cover: 'path/to/cover/image' },
        articles: [],
        letters: []
      }
    ];

const issuesData = data.map(item => item.data);
console.log(issuesData);

map() creates a new array from calling a function for every array element. map() calls a function once for each element in an array.