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How to transform an indexed array into an associative array? [duplicate]

This question already has answers here:
From an array of objects, extract value of a property as array
(24 answers)
Convert array of objects into array of properties [duplicate]
(4 answers)
Closed 2 years ago.
Is there a way to transform the following array of objects:
array = [
{ date: "08/18", id: 1 },
{ date: "08/14", id: 2 },
{ date: "08/15", id: 3 }
]
Into this? Only returning the dates:
array2 = ["08/18", "08/14", "08/15"]
I've been trying to push the date elements as it follows, but it doesn's seem to work:
array.map(e => {
array2.push(e.date)
})
Thanks in advance.

You can use the array map function:
array2 = array.map(object => object.date);

Array of flat objects, extract values of a all properties into single object of arrays [duplicate]

This question already has answers here:
best way to convert object with arrays to array with objects and viceversa
(4 answers)
Convert array of objects to object of arrays using lodash
(2 answers)
Closed 2 years ago.
I would like to go from this:
[{
"uuid": 'oaiwngoiasofoi328',
"property1": 3,
"property2": 3,
...many
},
...many ]
to this:
{
"uuid": ['oaiwngoiasofoi328','829rh83hr9h9h29','mejieoainfoi',...],
"property1": [3,3,2,...],
"property2": [3,3,2,...],
...many
}
all the properties will be named the same in each object of the source array
maybe I could use a for loop with map... ??

I've recreated your environment. I think it can help you.
Use Array.reduce() to reduce it to single object.
const data = [
{
uuid: 'adadkljalkd',
'property1': 3,
'property2': 4,
},
{
uuid: 'alkisdfj',
'property1': 4,
'property2': 5,
},
{
uuid: 'klilkkll',
'property1': 7,
'property2': 8,
}
];
const res = data.reduce((acc, obj) => {
Object.keys(obj).forEach(key => {
acc[key] = acc[key] || [];
acc[key].push(obj[key]);
})
return acc;
}, {});
console.log(res);

Filtering specific values on json array and create another array [duplicate]

This question already has answers here:
From an array of objects, extract value of a property as array
(24 answers)
Closed 3 years ago.
How can i create another array by filtering one json array and include just the values pairs of a specific key?
Example (Filtering Value Pairs of Number Keys):
Array:
{ Name: 'abcd', Number: '1234' },
{ Name: 'efgh', Number: '5678' }
]````
Result Array:
````var filteredarray = ['1234','5678'];````
Thanks!

const a = [
{ Name: 'abcd', Number: '1234' },
{ Name: 'efgh', Number: '5678' }
]
function getNumbers(){
return a.map(item => item.Number);
}
getNumbers();

Convert a Javascript array to a JSON object [duplicate]

This question already has answers here:
Javascript string array to object [duplicate]
(4 answers)
Convert array of strings into an array of objects
(6 answers)
JS : Convert Array of Strings to Array of Objects
(1 answer)
Closed 3 years ago.
How do I take a javascript array
var array = [1,2,3,4,5,6]
And convert it to a JSON object that looks like this
[
{
"value": 1
},
{
"value": 2
},
{
"value": 3
},
{
"value": 4
},
{
"value": 5
},
{
"value": 6
}
]
The closest I've come is using this
JSON.stringify(Object.assign({}, array));
But it gives me an output like this
{"0":1,"1":2,"2":3,"3":4,"4":5,"5":6}

You could map the values by taking a short hand property.
var array = [1, 2, 3, 4, 5, 6],
result = array.map(value => ({ value }));
console.log(result);

How to transform an array into a new array [duplicate]

This question already has answers here:
Changing the key name in an array of objects?
(11 answers)
Closed 5 years ago.
How can I transform values from an array to a new array?
I have an array like:
[
{ "amount" : 10, "date" : "2017-05-30" }...
]
which I want to "transform" into
[
{ x : 10, y: 2017-05-30 }
]
any help is appreciated...

You could map new objects with the new properties.
var array = [{ amount: 10, date: "2017-05-30" }],
newArray = array.map(a => ({ x: a.amount, y: a.date }));
console.log(newArray);

Using Array#map()
The callback function will create a new object with the 2 properties needed. You just have to keep the value of the current array
const array = [{ "amount" : 10, "date" : "2017-05-30" }];
let newArray = array.map(_=>({x:_.amount,y:_.date}));
console.log(newArray);

You can try using lodash map Lodash map
It will be something like:
const array2 = _.map(array1, (item) => { x: item.amount, y: item.date });