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/Crystal

module HTML

Overview

Provides HTML escaping and unescaping methods.

For HTML parsing see module XML, especially XML.parse_html.

NOTE To use HTML, you must explicitly import it with require "html"

Defined in:

html.cr
html/entities.cr

Class Method Summary

Class Method Detail

def self.escape(string : String, io : IO) : NilSource

Same as .escape(string) but outputs the result to the given io.

require "html"

io = IO::Memory.new
HTML.escape("Crystal & You", io) # => nil
io.to_s                          # => "Crystal & You"

def self.escape(string : Bytes, io : IO) : NilSource

Same as .escape(String, IO) but accepts Bytes instead of String.

The slice is assumed to be valid UTF-8.

def self.escape(string : String) : StringSource

Escapes special characters in HTML, namely &, <, >, " and '.

require "html"

HTML.escape("Crystal & You") # => "Crystal &amp; You"

def self.unescape(string : String) : StringSource

Returns a string where named and numeric character references (e.g. &gt;, &#62;, &#x3e;) in string are replaced with the corresponding unicode characters. This method decodes all HTML5 entities including those without a trailing semicolon (such as "&copy").

require "html"

HTML.unescape("Crystal &amp; You") # => "Crystal & You"

© 2012–2026 Manas Technology Solutions.
Licensed under the Apache License, Version 2.0.
https://crystal-lang.org/api/1.19.0/HTML.html