如何将具有两个键/值对的对象推入数组？

Question

I want to take this array as an argument

var movies = ['matrix','the dark knight','a beautiful mind','american pie']

for a function that loops through that array and pushes the titles as object into a new array adding an id (from the loop index) along the way.

The new arr should look like this

['{title:matrix, id:0}','{title:the dark knight, id:1}','{title:a beautiful mind, id:2}','{title:american pie, id:3}']

This is the function and I know I have a syntax error. But where?

function addToList(arr) {
    var movieList = []

    for (var x of arr) {
        movieList{["titel"]=arr, ["id"]=x}
    }
    return movieList
}

Answer 1

You can simply use .map() to get the desired output:

 const data = ['matrix','the dark knight','a beautiful mind','american pie'] const result = data.map((m, i) => ({title: m, id: i})); console.log(result); 

 .as-console-wrapper { max-height: 100% !important; top: 0; } 

Answer 2

Without using array.map

 function addToList(arr) {
        var movieList = []

        for (var i in arr) {
            movieList[i]={title:arr[i], id:i}
        }
        return movieList
    }

OR

function addToList(arr) {
    var movieList = []

    for (var i in arr) {
        movieList.push({title:arr[i], id:i});
    }
    return movieList
}

Answer 3

 function addToList(arr) { var movieList = [] for (var x of arr) { movieList.push({titel: arr, id: x}); } return movieList } 

Answer 4

for...of statement iterates over values of the object, not the indices (properties).

You can use for...in statement to iterate over indices (properties) of the object.

 var movies = ['matrix','the dark knight','a beautiful mind','american pie']; function addToList(arr) { var movieList = []; for (var i in arr) { movieList[i] = {"title": arr[i], "id": i}; } return movieList; } console.log(addToList(movies));