I have this array of objects

[ { id: '573267d06b2957ab24c54d59' },
  { id: '573267d06b2957ab24c54d5a' },
  { id: '573267d06b2957ab24c54d5b' },
  { id: '573267d06b2957ab24c54d5c' },
  { id: '573267d06b2957ab24c54d5d' } 
]

I wish to convert it to the following in NodeJs

[ '573267d06b2957ab24c54d59',
  '573267d06b2957ab24c54d5a',
  '573267d06b2957ab24c54d5b',
  '573267d06b2957ab24c54d5c',
  '573267d06b2957ab24c54d5d'
]

It seems like it should be easy given the right library/package, but I am struggling to find the right wording to "flatten" the array into the IDs of the contained objects.

I have this array of objects

[ { id: '573267d06b2957ab24c54d59' },
  { id: '573267d06b2957ab24c54d5a' },
  { id: '573267d06b2957ab24c54d5b' },
  { id: '573267d06b2957ab24c54d5c' },
  { id: '573267d06b2957ab24c54d5d' } 
]

I wish to convert it to the following in NodeJs

[ '573267d06b2957ab24c54d59',
  '573267d06b2957ab24c54d5a',
  '573267d06b2957ab24c54d5b',
  '573267d06b2957ab24c54d5c',
  '573267d06b2957ab24c54d5d'
]

It seems like it should be easy given the right library/package, but I am struggling to find the right wording to "flatten" the array into the IDs of the contained objects.

• javascript
• arrays
• node.js

• If you want to use a library, go for lodash (lodash./docs#flatten). Though you might have to find a function which works for your case. – Vikram Tiwari Commented May 10, 2016 at 23:33
• Thanks for the suggestion. I don't need to use a library, just thought that it's the kind of that that a library might be useful for. – Jake N Commented May 11, 2016 at 8:33

1 Answer 1

Say your array of objects is called arr, just do this:

var arrayOfStrings = arr.map(function(obj) {
    return obj.id;
});

map will iterate over the array and create a new array based on how you define your function. In this case we return the value of the id key in each case to build out the desired array of ids.