I'm sure it's somewhere inside the LoDash docs, but I can't seem to find the right combination.
var users = [{
id: 12,
name: 'Adam'
},{
id: 14,
name: 'Bob'
},{
id: 16,
name: 'Charlie'
},{
id: 18,
name: 'David'
}
]
// how do I get [12, 14, 16, 18]
var userIds = _.map(users, _.pick('id'));
Since version v4.x you should use _.map:
_.map(users, 'id'); // [12, 14, 16, 18]
this way it is corresponds to native Array.prototype.map method where you would write (ES2015 syntax):
users.map(user => user.id); // [12, 14, 16, 18]
Before v4.x you could use _.pluck the same way:
_.pluck(users, 'id'); // [12, 14, 16, 18]
_.toArray(_.mapValues(users, 'id'))
users.map(({ id, name }) => ({ id, name })) or less cryptic users.map(user => ({ id: user.id, name: user.name })). Same in lodash: _.map(users, ({ id, name }) => ({ id, name })).
In the new lodash release v4.0.0 _.pluck has removed in favor of _.map
Then you can use this:
_.map(users, 'id'); // [12, 14, 16, 18]
You can see in Github Changelog
With pure JS:
var userIds = users.map( function(obj) { return obj.id; } );
Simple and even faster way to get it via ES6
let newArray = users.flatMap(i => i.ID) // -> [ 12, 13, 14, 15 ]
flatMap() instead of map()?
map() is exist for object manipulation where flatMap() just for softing your Array<Object> to single arraymap() and flatMap(). Just wanted to know why you suggested flatMap() in this case when there are already answers with map(). Would be great if you can elaborate when we should use flatMap() instead of map().If you are using native javascript then you can use this code -
let ids = users.map(function(obj, index) {
return obj.id;
})
console.log(ids); //[12, 14, 16, 18]
const users = [{
id: 12,
name: 'Adam'
},{
id: 14,
name: 'Bob'
},{
id: 16,
name: 'Charlie'
},{
id: 18,
name: 'David'
}
]
const userIds = _.values(users);
console.log(userIds); //[12, 14, 16, 18]
This will give you what you want in a pop-up.
for(var i = 0; i < users.Count; i++){
alert(users[i].id);
}
