JavaScript Date prototype Property

Date Object Reference JavaScript Date Object


Make a new date method that gives the date object a month-name property called myProp:

Date.prototype.myMet = function() {
    if (this.getMonth() == 0){this.myProp = "January"};
    if (this.getMonth() == 1){this.myProp = "February"};
    if (this.getMonth() == 2){this.myProp = "March"};
    if (this.getMonth() == 3){this.myProp = "April"};
    if (this.getMonth() == 4){this.myProp = "May"};
    if (this.getMonth() == 5){this.myProp = "June"};
    if (this.getMonth() == 6){this.myProp = "July"};
    if (this.getMonth() == 7){this.myProp = "August"};
    if (this.getMonth() == 8){this.myProp = "Spetember"};
    if (this.getMonth() == 9){this.myProp = "October"};
    if (this.getMonth() == 10){this.myProp = "November"};
    if (this.getMonth() == 11){this.myProp = "December"};

Make a Date object, then call the myMet method:

var d = new Date();
var monthname = d.myProp;

The result of monthname will be:

Try it yourself »

Definition and Usage

The prototype constructor allows you to add new properties and methods to the Date() object.

When constructing a property, ALL date objects will be given the property, and it's value, as default.

When constructing a method, ALL date objects will have this method available.

Note: Date.prototype does not refer to a single date object, but to the Date() object itself.

Note: Prototype is a global object constructor which is available for all JavaScript objects.

Browser Support

prototype Yes Yes Yes Yes Yes


Technical Details

JavaScript Version: 1.1

Date Object Reference JavaScript Date Object


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