从Array对象中获取关键数据，并将其转换为一个分隔的字符串

Question

What method, or lodash function would you use to pull out the ids below and generate a comma separated string out of them?

var myArray = [
    {
        tag: 'wunwun',
        id: 132
    },
    {
        tag: 'davos',
        id: 452
    },
    {
        tag: 'jon snow',
        id: 678
    }
]

---

Like this: '132, '452', '678'

Answer 1

No need to use a third-party library for that:

var commaSeparatedIds = myArray.map(function(item) {
    return item.id;
}).join(','); // result: '132,452,678'

Or if you just want them as an array, skip the join :

var commaSeparatedIds = myArray.map(function(item) {
    return item.id;
}); // result: ['132', '452', '678']

References:

• Array.prototype.join()
• Array.prototype.map()

Answer 2

Use Array#map to get array of id and apply Array#join over it.

 var myArray = [{ tag: 'wunwun', id: 132 }, { tag: 'davos', id: 452 }, { tag: 'jon snow', id: 678 }]; var op = myArray.map(function(item) { return item.id; }); console.log(op.join(', ')) 

Answer 3

Well, this is easy:

_.pluck(myArray, 'id').join(', ')

_.map works the same way, but you can also pass in a function instead of an array

Answer 4

myArray.map(function(element){return element.id;}).join(',');