add element to array without at a certain inded code example

Example 1: javascript insert item into array

var colors=["red","blue"];
var index=1;

//insert "white" at index 1
colors.splice(index, 0, "white");   //colors =  ["red", "white", "blue"]

Example 2: add an object to index 0 array js

//Add an object to start of array
splice(index,noOfItemstoDelete,item);
ex - arr.splice(0,0,item);