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Other References

CSSStyleDeclaration JS Conversion


Prototipo de número de JavaScript

Ejemplo

Cree un nuevo método numérico que devuelva la mitad del valor de un número:

Number.prototype.myMethod = function() {
  return this.valueOf() / 2;
};

Utilice el nuevo método en un número:

let n = 55;
let x = n.myMethod();

Definición y uso

prototypele permite agregar nuevas propiedades y métodos a los números.

prototypees una propiedad disponible con todos los objetos de JavaScript.


Sintaxis

Number.prototype.name = value


Advertencia

No se le recomienda cambiar el prototipo de un objeto que no controla.

No debe cambiar el prototipo de tipos de datos de JavaScript incorporados como:

  • Números
  • Instrumentos de cuerda
  • arreglos
  • fechas
  • Booleanos
  • Función
  • Objetos

Solo cambie el prototipo de sus propios objetos.

La propiedad prototipo

La propiedad de JavaScript prototypele permite agregar nuevas propiedades a los objetos:

Ejemplo

function Person(first, last, age, eyecolor) {
  this.firstName = first;
  this.lastName = last;
  this.eyeColor = eyecolor;
}

Person.prototype.nationality = "English";

Compatibilidad con navegador

Number.prototypees una característica de ECMAScript1 (ES1).

ES1 (JavaScript 1997) es totalmente compatible con todos los navegadores:

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