I have an arrays of objects, lets say
[{a:'one',aa:'eleven'},{a:'two',aa:'twelve'},{a:'three',aa:'thirteen'}]
I want to convert the objects into arrays, something like this
[['one','eleven'], ['two','twelve'],['three','thirteen']]
as property name should map to a given correct index in the array
Is this possible using Lodash or javascript?
If certain keys in the original objects must go to specific slots in the array, then you can create a map of key to slot number.
var data = [{
a: 'one',
aa: 'eleven'
}, {
a: 'two',
aa: 'twelve'
}, {
a: 'three',
aa: 'thirteen'
}];
var keyToSlot = {
a: 0,
aa: 1
};
var result = data.map(function(entry) {
var keys = Object.keys(entry);
return keys.reduce(function(acc, key) {
var slot = keyToSlot[key];
acc[slot] = entry[key];
return acc;
}, []);
});
console.log(result);You can do this by grabbing the keys of every object, sorting them, and then mapping them to an array.
const arr = [{a:'one',aa:'eleven'},{a:'two',aa:'twelve'},{a:'three',aa:'thirteen'}]
const res = arr.map(x => Object.keys(x).sort().map(y => x[y]));
console.log(res)Step by step:
arr.map iterates through each object
Object.keys(x).sort() gets the keys of the object and sorts them alphabetically..map(y => x[y]) on the above result turns the keys of the objects into the respective values.
sort() call on the keys guarantees order does it not? You need to specify some way to sort the keys, and in this case I chose alphabetical.Here's a an approach using lodash#map with a lodash#unary wrapped lodash#map iteratee.
var result = _.map(data, _.unary(_.map));
var data = [{a:'one',aa:'eleven'},{a:'two',aa:'twelve'},{a:'three',aa:'thirteen'}];
var result = _.map(data, _.unary(_.map));
console.log(result);body > div { min-height: 100%; top: 0; }<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.js"></script>Update
To preserve key orders, you may replace the lodash#map iteratee into lodash#at that is partially applied with the keys that defines the order of the values.
var keys = ['aa', 'a'];
var result = _.map(data, _.unary(_.partialRight(_.at, keys)));
var data = [{a:'one',aa:'eleven'},{a:'two',aa:'twelve'},{a:'three',aa:'thirteen'}];
var keys = ['aa', 'a'];
var result = _.map(data, _.unary(_.partialRight(_.at, keys)));
console.log(result);body > div { min-height: 100%; top: 0; }<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.js"></script>An es6 alternative of the solution above would be:
var keys = ['aa', 'a'];
var result = _.map(data, v => _.at(v, keys));
var data = [{a:'one',aa:'eleven'},{a:'two',aa:'twelve'},{a:'three',aa:'thirteen'}];
var keys = ['aa', 'a'];
var result = _.map(data, v => _.at(v, keys));
console.log(result);body > div { min-height: 100%; top: 0; }<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.js"></script>
sortmay not be correct :)