What is the JavaScript ternary operator?

The ternary operator is a JavaScript Operator which will return one of two values depending on a conditional supplied. Basically, you supply any conditional which will evaluate out to true or false and it will return one of the two expressions. It is set  up as such:

condition ? expression1 : expression2

If the condition evaluates true, then expression1 is returned. If the condition evaluates to false, then expression2 is returned.


var pet = {
    name: "Spot",
    species: "Dog"
var soundMakes = pet.species === "Dog" ? "woof" : "meow";
//expected output: "woof"

You can use multiple conditions when evaluating. And you can put functions in the expression section to run complex code.


var aDog = true;
var myPet = false;

aDog && myPet ? function() {
    alert("It's my dog");
    console.log('Give the dog a treat');
} ()
function () {
    alert("Not my dog");
    console.log('Walk away quickly');
} ();

For more information:

JavaScript — delete a property from an object

You can remove a property from a JavaScript object with the delete operator.

And it’s super easy:

delete object.property
var Car = {
    make: "Mazda",
    model: "CX-5",
    year: "2014"

// expected output: "2014"

delete Car.year;

// expected output: undefined

For more information: