You want the splice
function on the native array object.
arr.splice(index, 0, item);
will insert item
into arr
at the specified index
(deleting 0
items first, that is, it's just an insert).
In this example we will create an array and add an element to it into index 2:
var arr = []; arr[0] = "Jani"; arr[1] = "Hege"; arr[2] = "Stale"; arr[3] = "Kai Jim"; arr[4] = "Borge"; console.log(arr.join()); // Jani,Hege,Stale,Kai Jim,Borge arr.splice(2, 0, "Lene"); console.log(arr.join()); // Jani,Hege,Lene,Stale,Kai Jim,Borge