JavaScript: The Definitive Guide, Fourth Edition

Name

encodeURIComponent( ) — escape characters in a URI component

Availability

JavaScript 1.5; JScript 5.5; ECMAScript v3

Synopsis

encodeURIComponent(s)

Arguments

s

A string that contains a portion of a URI or other text to be encoded.

Returns

A copy of s, with certain characters replaced by hexadecimal escape sequences.

Throws

URIError

Indicates that s contains malformed Unicode surrogate pairs and cannot be encoded.

Description

encodeURIComponent( ) is a global function that returns an encoded copy of its s argument. ASCII letters and digits are not encoded, nor are the following ASCII punctuation characters:

- _ . ! ~ * ' ( )

All other characters, including punctuation characters such as /, :, # that serve to separate the various components of a URI, are replaced with one or more hexadecimal escape sequences. See encodeURI( ) for a description of the encoding scheme used.

Note the difference between encodeURIComponent( ) and encodeURI( ): encodeURIComponent( ) assumes that its argument is a portion (such as the protocol, hostname, path, or query string) of a URI. Therefore it escapes the punctuation characters that are used to separate the portions of a URI.

Example

encodeURIComponent("hello world?");  // Returns hello%20world%3F

See Also

decodeURI( ), decodeURIComponent( ), encodeURI( ), escape( ), unescape( )