{"id":7521,"date":"2020-01-30T15:23:25","date_gmt":"2020-01-30T15:23:25","guid":{"rendered":"https:\/\/www.jose-aguilar.com\/blog\/?p=7521"},"modified":"2020-01-30T15:23:25","modified_gmt":"2020-01-30T15:23:25","slug":"crear-variables-en-javascript-diferencias-entre-var-let-y-const","status":"publish","type":"post","link":"https:\/\/www.jose-aguilar.com\/blog\/crear-variables-en-javascript-diferencias-entre-var-let-y-const\/","title":{"rendered":"Crear variables en JavaScript – Diferencias entre var, let y const"},"content":{"rendered":"

Se puede usar var<\/em>, let<\/em> y const<\/em> para crear variables en JavaScript<\/strong>.<\/p>\n

var<\/em> es como la versi\u00f3n anterior para crear variables.<\/p>\n

let<\/em> y const<\/em> son las nuevas formas de crear variables y en las \u00faltimas versiones de cualquier navegador ya son soportadas.<\/p>\n

No tienes que hacer nada especial. Solo tienes que crearlas y ya deber\u00edan funcionar en tu c\u00f3digo.<\/p>\n

\u00bfC\u00f3mo crear una variable en JavaScript con var?<\/h2>\n

Esta forma se ha utilizado desde los inicios de JavaScript<\/strong> y, a d\u00eda de hoy, todav\u00eda est\u00e1 permitido usarlo en tu c\u00f3digo para la creaci\u00f3n de variables.<\/p>\n

Puedes crear una variable con var<\/em> en JavaScript<\/strong> de la siguiente forma:<\/p>\n

<\/a>Source code<\/a><\/td><\/a> <\/a> <\/a> <\/td><\/tr><\/table><\/div>
var<\/span> firstname =<\/span> 'Jose'<\/span>;<\/span><\/pre><\/div><\/div>\n
 <\/p>\n
Esto todav\u00eda funciona pero no lo recomiendo actualmente.<\/p>\n
\u00bfC\u00f3mo crear una variable en JavaScript con let?<\/h2>\n
La posibilidad de crear una variable con let<\/em> no permite volver a declarar variables pero si cambiar su valor.<\/p>\n
Esta es la principal diferencia con var<\/em>, que si permite re declarar la variable de nuevo.<\/p>\n
Puedes crear una variable con let<\/em> en JavaScript<\/strong> de la siguiente forma:<\/p>\n
<\/a>Source code<\/a><\/td><\/a> <\/a> <\/a> <\/td><\/tr><\/table><\/div>
let firstname =<\/span> 'Jose'<\/span>;<\/span><\/pre><\/div><\/div>\n
 <\/p>\n
Recomendaci\u00f3n: usa let<\/em> siempre que el valor vaya a cambiar en un futuro.<\/p>\n
\u00bfC\u00f3mo crear una variable en JavaScript con const?<\/h2>\n
const<\/em> se emplea para crear contantes.<\/p>\n
En realidad, no es una variable ya que su valor no puede ser cambiado en la secuencia del script.<\/p>\n
Puedes crear una constante con const<\/em> en JavaScript<\/strong> de la siguiente forma:<\/p>\n
<\/a>Source code<\/a><\/td><\/a> <\/a> <\/a> <\/td><\/tr><\/table><\/div>
const<\/span> firstname =<\/span> 'Jose'<\/span>;<\/span><\/pre><\/div><\/div>\n
Recomendaci\u00f3n: usa const<\/em> cuando sabes que el valor no va a cambiar en la secuencia de tu c\u00f3digo.<\/p>\n","protected":false},"excerpt":{"rendered":"
Aprente como crear variables y constantes en JavaScript. Descubre las diferencias entre var, let y const. JavaScript moderno.<\/p>\n","protected":false},"author":1,"featured_media":7523,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[14],"tags":[],"class_list":["post-7521","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-javascript"],"yoast_head":"\nCrear variables en JavaScript - Diferencias entre var, let y const - Jose Aguilar Blog<\/title>\n<meta name=\"description\" content=\"Aprente como crear variables y constantes en JavaScript. Descubre las diferencias entre var, let y const. 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