JAVASCRIPT

Delete Properties from a JavaScript Object

var ourDog = {
  "name": "Camper",
  "legs": 4,
  "tails": 1,
  "friends": ["everything!"],
  "bark": "bow-wow"
};

delete ourDog.bark;

how to delete object properties in javascript

// Creates a new object, myobj, with two properties, a and b.
var myobj = new Object;
myobj.a = 5;
myobj.b = 12;

// Removes the a property, leaving myobj with only the b property.
delete myobj.a;
console.log ('a' in myobj); // output: "false"

delete all properties from an javascript object

req.session.user = { name: 'Alexander' };  // we store an object in the session
var session = req.session;                 // save reference to the session in a variable
console.log( req.session, session );       // {user: Object}, {user: Object}

req.session = {};                          // let's replace session with a new object
console.log( req.session, session );       // {}, {user: Object}

Delete object properties in JavaScript

for (var k in myObj) {
    if (k !== 'p1' && k !== 'p2' && k !== 'p100') {
        delete myObj[k];
    }
}