how to remove an item from javascript object code example

Example 1: javascript remove property from object

var person = {"first_name": "Billy","last_name": "Johnson"};
delete person.last_name; //delete last_name property

Example 2: javascript remove element from object

delete object.element

Example 3: js remove key from object

// Example 1
var key = "Cow";
delete thisIsObject[key]; 

// Example 2
delete thisIsObject["Cow"];

// Example 3
delete thisIsObject.Cow;