Javascript: delete property from object & element from array

As we are working with object or array, sometimes, we need to delete it’s property of element. Below is an example of a simple way to do it.

var display_before = function (str){
    return "before delete " + str;
}

var display_after = function (str){
    return "after delete " + str;
}

var obj = {x:12, y:15};
console.log(display_before("obj.x") + " " + obj.x);

//delete property x from object
delete obj.x;
console.log(display_after("obj.x") + " " + obj.x);

//delete array[2]
var array = [2, 4, 6, 8, 10]
console.log(display_before("array: ") + array);

array.splice(2,1);    //delete value 6 from array
console.log(display_after("index 2 from array: ") + array);

Sample result (in firebug plugin):