Replacing Array element with same index in javascript

Question

I have an Array like

var myArray = new Array;

I have to push some elements to array in such a way that the elements will be replaced with same index.

Example :

myArray.push(1);
myArray.push(2);
myArray.push(3);

so now

myArray[0] = 1
myArray[1] = 2

now when i will push element 3 then myArray[0] will be replaced with 3 and myArray[1] will be replaced with 1 and the element 2 will be removed.

It will continue according to the number of elements pushed...

Can any body help me with this requirement...

possible answer: similar stack http://stackoverflow.com/questions/14236515/can-i-limit-the-length-of-an-array-in-javascript — yjs, Dec 14 '15 at 12:44
I made a little JSfiddle to you : http://jsfiddle.net/10woyacm/ — Akram Saouri, Dec 14 '15 at 12:51

Andy · Accepted Answer · 2015-12-14T12:58:42.720

push adds to the end of an array. If you want to add a value to the beginning of an array you can use unshift.

myArray.unshift(3);

You can then use pop to remove the last element:

arr.pop();

DEMO

However, what you might need, given that you need to remove the same number of elements from an array that you add is a function that uses concat and slice instead:

function pusher(arr, add) {
  return add.concat(arr).slice(0, arr.length);
}

var arr = [1, 2, 3, 4];
var arr = pusher(arr, [5, 6]); // [5, 6, 1, 2]

DEMO

score 0 · Answer 2 · answered Dec 14 '15 at 12:47

0

I think you need something in the lines of:

myArray.unshift(element);
myArray.pop();

Explanation:

unshift: inserts the element on position 0 and moves all other elements one position to the right
pop: removes last element from array

answered Dec 14 '15 at 12:47

Octav Zlatior

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Replacing Array element with same index in javascript

2 Answers2