Problem with Accesing array data Javascript

Question

I want to access data of var a so it is: 245 but instead it only accesses the last one. so if i print it out it says 5

var A = [1, 2, 3, 4, 5];
var B = A[[1], [3], [4]];
console.log(B)

Answer 1

When accessing an object using square bracket notation — object[expression] — the expression resolves to the string name of the property.

The expression [1], [3], [4] consists of three array literals separated by comma operators. So it becomes [4]. Then it gets converted to a string: "4". Hence your result.

JavaScript doesn't have any syntax for picking non-contiguous members of an array in a single operation. (For contiguous members you have the slice method.)

You need to get the values one by one.

var A = [1, 2, 3, 4, 5];
var B = [A[1], A[3], A[4]];
console.log(B.join(""))

Answer 2

var A = [1, 2, 3, 4, 5];
var B = [A[1], A[3], A[4]];
console.log(B)

• Ali Mohammed: i tried this but i didn't put bracket notation before the first one so it was A[[1], A[3], [4]] I shouldve thought about that

Answer 3

You'll need to access A multiple times for each index.

var A = [1, 2, 3, 4, 5];
var B = A[1];
console.log(A[1], A[3], A[4])

Answer 4

You can access them directly like that. If you want to access index 2 for example, you should do console.log(A[1]); You can't access multiple indices at the same time. A variable can have only one value.

Answer 5

@Quentin solution resolve the problem, I wrote this solution to recommend you to create an array of index, and iterate over it.

Note: You are getting the last index, because you are using the comma operator. The comma operator allows you to put multiple expressions. The resulting will be the value of the last comma separated expression.

const A = [1, 2, 3, 4, 5];
const indexes = [1,3,4];
const B = indexes.map(i => A[i]).join``;
console.log(B);