I have a requirement to parse an object and convert in to an array using Underscore/Lo-Dash

Tried using usersocre, but its not getting expected result. Sorry am new to underscore js. Your help is much appreciated.

var arr = _.values(obj)

var obj = {
    '2c13790be20a06a35da629c71e548afexing': [{
        connector: '',
        displayName: 'John',
        loginName: '',
        userImage: '2.jpg'
    }],
    '493353a4c5f0aa71508d4055483ff979linkedinpage': [{
        connector: '',
        displayName: 'Mak',
        loginName: '',
        userImage: '1.jpg'
    }]
}

expected output array

array = [{
    connector: '2c13790be20a06a35da629c71e548afexing',
    displayName: 'John',
    loginName: '',
    userImage: '2.jpg'
}, {
    connector: '493353a4c5f0aa71508d4055483ff979linkedinpage',
    displayName: 'Mak',
    loginName: '',
    userImage: '1.jpg'
}]

I have a requirement to parse an object and convert in to an array using Underscore/Lo-Dash

Tried using usersocre, but its not getting expected result. Sorry am new to underscore js. Your help is much appreciated.

var arr = _.values(obj)

var obj = {
    '2c13790be20a06a35da629c71e548afexing': [{
        connector: '',
        displayName: 'John',
        loginName: '',
        userImage: '2.jpg'
    }],
    '493353a4c5f0aa71508d4055483ff979linkedinpage': [{
        connector: '',
        displayName: 'Mak',
        loginName: '',
        userImage: '1.jpg'
    }]
}

expected output array

array = [{
    connector: '2c13790be20a06a35da629c71e548afexing',
    displayName: 'John',
    loginName: '',
    userImage: '2.jpg'
}, {
    connector: '493353a4c5f0aa71508d4055483ff979linkedinpage',
    displayName: 'Mak',
    loginName: '',
    userImage: '1.jpg'
}]

• javascript
• underscore.js
• lodash

• There's no "parsing" going on there. You're just accessing data in one object and transforming into another object. Anyway, in cases like this where you're stuck I'd recommend sitting down and writing out what you think you need to in native language. For example, "Create an array. Each element of the array will be an object, ....". That could help you get started. – user663031 Commented Nov 28, 2015 at 4:15

4 Answers 4

Use Object.keys with forEach and add object in the array.

1. Get all the keys of the object
2. Iterate over the keys array using forEach
3. Push first element of the subarray in the result array.

Code:

var arr = [];
Object.keys(obj).forEach(function(e) {
    // Get the key and assign it to `connector`
    obj[e][0].connector = e;
    arr.push(obj[e][0]);
});

var obj = {
  '2c13790be20a06a35da629c71e548afexing': [{
    connector: '',
    displayName: 'John',
    loginName: '',
    userImage: '2.jpg'
  }],
  '493353a4c5f0aa71508d4055483ff979linkedinpage': [{
    connector: '',
    displayName: 'Mak',
    loginName: '',
    userImage: '1.jpg'
  }]
};

var arr = [];
Object.keys(obj).forEach(function(e) {
  obj[e][0].connector = e;
  arr.push(obj[e][0]);
});

console.log(arr);
document.getElementById('output').innerHTML = JSON.stringify(arr, 0, 4);

<pre id="output"></pre>

The same code be converted to use Lodash/Underscore's forEach.

var arr = [];
_.forEach(obj, function(e, k) {
    e[0].connector = k;
    arr.push(e[0]);
});

var obj = {
  '2c13790be20a06a35da629c71e548afexing': [{
    connector: '',
    displayName: 'John',
    loginName: '',
    userImage: '2.jpg'
  }],
  '493353a4c5f0aa71508d4055483ff979linkedinpage': [{
    connector: '',
    displayName: 'Mak',
    loginName: '',
    userImage: '1.jpg'
  }]
};

var arr = [];

_.forEach(obj, function(e, k) {
  e[0].connector = k;
  arr.push(e[0]);
});

console.log(arr);
document.getElementById('output').innerHTML = JSON.stringify(arr, 0, 4);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/3.10.1/lodash.js"></script>
<pre id="output"></pre>

You can go like this in Underscore:

_(obj).each(function(elem, key){
   arr.push(elem[0]);
});

See it in action

If you're talking about functional, I usually don't want to alter the original object in any way, so I use extend to create a new object. I overwrite the connector property in the next line and return the object.

_.map(function( arr, key ) {
  var obj = _.extend({}, arr.pop());
  obj.connector = key;
  return obj;
});

Grab the object from the first value in each key's array and assign the key to the connector property. No library needed.

var result = [];
for (key in obj) {
    result.push(obj[key][0]);
    result[result.length-1]["connector"] = key; 
}