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Other References

CSSStyleDeclaration JS Conversion


JavaScript Array prototype

Example

Create a method that transforms array values into upper case:

Array.prototype.myUcase = function() {
  for (let i = 0; i < this.length; i++) {
    this[i] = this[i].toUpperCase();
  }
};

Use the method on any array:

var fruits = ["Banana", "Orange", "Apple", "Mango"];
fruits.myUcase();
Try it Yourself »

Definition and Usage

prototype allows you to add new properties and methods to arrays.

prototype is a global property which is available with all JavaScript objects.


Syntax

Array.prototype.name = value

Browser Support

prototype is an ES1 feature (JavaScript 1997). It is fully supported in all browsers:

Chrome IE Edge Firefox Safari Opera
Yes Yes Yes Yes Yes Yes