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JavaScript Boolean prototype Constructor

JavaScript Boolean Reference JavaScript Boolean Reference

Example

Make a new method for JavaScript booleans:

Boolean.prototype.myColor = function() {
    if (this.valueOf() == true) {
        return "green";
    } else {
        return = "red";
    }
}

Create a boolean, then call myColor():

var a = true;
var b = a.myColor();

The value of b is now:

green

Try it yourself »


Definition and Usage

The prototype constructor allows you to add new properties and methods to JavaScript booleans.

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

When constructing a method, ALL booleans will have this method available.

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

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


Browser Support

Internet Explorer Firefox Opera Google Chrome Safari

The prototype property is supported in all major browsers.


Syntax

Boolean.prototype.name = value


JavaScript Boolean Reference JavaScript Boolean Reference

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