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unescape()

Deprecated

Avoid using this feature in new projects. TC39 included the escape() and unescape() methods in Annex B of the ECMAScript specification, which covers JavaScript features with "one or more undesirable characteristics and in the absence of legacy usage would be removed." This feature may be a candidate for removal from web standards or browsers.

Nota: unescape() no es una funcin estndar implementada por los navegadores y solo se estandariz para la compatibilidad entre motores. No es necesario que todos los motores de JavaScript lo implementen y es posible que no funcione en todas partes. Use decodeURIComponent() o decodeURI() si es posible.

La funcin unescape() calcula una nueva cadena en la que las secuencias de escape hexadecimales se reemplazan con los caracteres que representan. Las secuencias de escape pueden ser introducidas por una funcin como escape().

In this article

Sintaxis

js
unescape(str)

Parmetros

str

Una cadena a decodificar.

Valor de retorno

Una nueva cadena en la que ciertos caracteres no han sido reemplazados.

Descripcin

unescape() es una propiedad de funcin del objeto global.

La funcin unescape() reemplaza cualquier secuencia de escape con el carcter que representa. Especficamente, reemplaza cualquier secuencia de escape de la forma %XX o %uXXXX (donde X representa un dgito hexadecimal) con el carcter que tiene el valor hexadecimal XX/XXXX. Si la secuencia de escape no es una secuencia de escape vlida (por ejemplo, si "%" va seguido de uno o ningn dgito hexadecimal), se deja como est.

Nota: Esta funcin se us principalmente para la codificacin de URL y se basa en parte en el formato de escape en RFC 1738. La funcin unescape() no evala secuencias de escape en cadenas literales. Puede reemplazar \xXX con %XX y \uXXXX con %uXXXX para obtener una cadena que unescape() pueda manejar.

Ejemplos

Utilizando unescape()

js
unescape("abc123"); // "abc123"
unescape("%E4%F6%FC"); // ""
unescape("%u0107"); // ""

Especificaciones

Specification
ECMAScript 2027 LanguageSpecification
# sec-unescape-string

Compatibilidad con navegadores

Vase tambin

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