Module: CGI::Escape
| Relationships & Source Files | |
| Extension / Inclusion / Inheritance Descendants | |
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Extended In:
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Included In:
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| Defined in: | lib/cgi/escape.rb, ext/cgi/escape/escape.c, lib/cgi/escape.rb |
Overview
Web-related escape/unescape functionality.
Constant Summary
-
TABLE_FOR_ESCAPE_HTML__ =
Internal use only
# File 'lib/cgi/escape.rb', line 80
The set of special characters and their escaped values
{ # :nodoc: "'" => ''', '&' => '&', '"' => '"', '<' => '<', '>' => '>', }
Instance Method Summary
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#escape(string)
URL-encode a string into application/x-www-form-urlencoded.
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#escape_element(string, *elements)
Alias for #escapeElement.
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#escape_uri_component(string)
Alias for #escapeURIComponent.
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#escapeElement(string, *elements)
(also: #escape_element)
Escape only the tags of certain HTML elements in
string. -
#escapeHTML(string)
Escape special characters in HTML, namely '&"<>.
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#escapeURIComponent(string)
(also: #escape_uri_component)
URL-encode a string following RFC 3986 Space characters (" ") are encoded with ("%20").
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#unescape(string, encoding = @@accept_charset)
URL-decode an application/x-www-form-urlencoded string with encoding(optional).
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#unescape_element(string, *elements)
Alias for #unescapeElement.
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#unescape_uri_component(string, encoding = @@accept_charset)
Alias for #unescapeURIComponent.
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#unescapeElement(string, *elements)
(also: #unescape_element)
Undo escaping such as that done by
CGI.escapeElement -
#unescapeHTML(string)
Unescape a string that has been HTML-escaped.
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#unescapeURIComponent(string, encoding = @@accept_charset)
(also: #unescape_uri_component)
URL-decode a string following RFC 3986 with encoding(optional).
Instance Method Details
#escape(string)
URL-encode a string into application/x-www-form-urlencoded. Space characters (" ") are encoded with plus signs ("+") url_encoded_string = CGI.escape("'Stop!' said Fred") # => "%27Stop%21%27+said+Fred"
# File 'lib/cgi/escape.rb', line 28
def escape(string) encoding = string.encoding buffer = string.b buffer.gsub!(/([^ a-zA-Z0-9_.\-~]+)/) do |m| '%' + m.unpack('H2' * m.bytesize).join('%').upcase end buffer.tr!(' ', '+') buffer.force_encoding(encoding) end
#escape_element(string, *elements)
Alias for #escapeElement.
# File 'lib/cgi/escape.rb', line 229
alias escape_element escapeElement
#escape_uri_component(string)
Alias for #escapeURIComponent.
# File 'lib/cgi/escape.rb', line 63
alias escape_uri_component escapeURIComponent
#escapeElement(string, *elements) Also known as: #escape_element
Escape only the tags of certain HTML elements in string.
Takes an element or elements or array of elements. Each element is specified by the name of the element, without angle brackets. This matches both the start and the end tag of that element. The attribute list of the open tag will also be escaped (for instance, the double-quotes surrounding attribute values).
print CGI.escapeElement('<BR><A HREF="url"></A>', "A", "IMG")
# "<BR><A HREF="url"></A>"
print CGI.escapeElement('<BR><A HREF="url"></A>', ["A", "IMG"])
# "<BR><A HREF="url"></A>"
# File 'lib/cgi/escape.rb', line 198
def escapeElement(string, *elements) elements = elements[0] if elements[0].kind_of?(Array) unless elements.empty? string.gsub(/<\/?(?:#{elements.join("|")})\b[^<>]*+>?/im) do CGI.escapeHTML($&) end else string end end
#escapeHTML(string)
Escape special characters in HTML, namely '&"<>
CGI.escapeHTML('Usage: foo "bar"
# File 'lib/cgi/escape.rb', line 91
def escapeHTML(string) enc = string.encoding unless enc.ascii_compatible? if enc.dummy? origenc = enc enc = Encoding::Converter.asciicompat_encoding(enc) string = enc ? string.encode(enc) : string.b end table = Hash[TABLE_FOR_ESCAPE_HTML__.map {|pair|pair.map {|s|s.encode(enc)}}] string = string.gsub(/#{"['&\"<>]".encode(enc)}/, table) string.encode!(origenc) if origenc string else string = string.b string.gsub!(/['&\"<>]/, TABLE_FOR_ESCAPE_HTML__) string.force_encoding(enc) end end
#escapeURIComponent(string) Also known as: #escape_uri_component
URL-encode a string following RFC 3986 Space characters (" ") are encoded with ("%20") url_encoded_string = CGI.escapeURIComponent("'Stop!' said Fred") # => "%27Stop%21%27%20said%20Fred"
# File 'lib/cgi/escape.rb', line 55
def escapeURIComponent(string) encoding = string.encoding buffer = string.b buffer.gsub!(/([^a-zA-Z0-9_.\-~]+)/) do |m| '%' + m.unpack('H2' * m.bytesize).join('%').upcase end buffer.force_encoding(encoding) end
#unescape(string, encoding = @@accept_charset)
URL-decode an application/x-www-form-urlencoded string with encoding(optional). string = CGI.unescape("%27Stop%21%27+said+Fred") # => "'Stop!' said Fred"
# File 'lib/cgi/escape.rb', line 41
def unescape(string, encoding = @@accept_charset) str = string.tr('+', ' ') str = str.b str.gsub!(/((?:%[0-9a-fA-F]{2})+)/) do |m| [m.delete('%')].pack('H*') end str.force_encoding(encoding) str.valid_encoding? ? str : str.force_encoding(string.encoding) end
#unescape_element(string, *elements)
Alias for #unescapeElement.
# File 'lib/cgi/escape.rb', line 231
alias unescape_element unescapeElement
#unescape_uri_component(string, encoding = @@accept_charset)
Alias for #unescapeURIComponent.
# File 'lib/cgi/escape.rb', line 77
alias unescape_uri_component unescapeURIComponent
#unescapeElement(string, *elements) Also known as: #unescape_element
Undo escaping such as that done by CGI.escapeElement
print CGI.unescapeElement(
CGI.escapeHTML('<BR><A HREF="url"></A>'), "A", "IMG")
# "<BR><A HREF="url"></A>"
print CGI.unescapeElement(
CGI.escapeHTML('<BR><A HREF="url"></A>'), ["A", "IMG"])
# "<BR><A HREF="url"></A>"
# File 'lib/cgi/escape.rb', line 218
def unescapeElement(string, *elements) elements = elements[0] if elements[0].kind_of?(Array) unless elements.empty? string.gsub(/<\/?(?:#{elements.join("|")})\b(?>[^&]|&(?![gl]t;)\w;)*(?:>)?/im) do unescapeHTML($&) end else string end end
#unescapeHTML(string)
Unescape a string that has been HTML-escaped
CGI.unescapeHTML("Usage: foo "bar" <baz>")
# => "Usage: foo "bar"
# File 'lib/cgi/escape.rb', line 113
def unescapeHTML(string) enc = string.encoding unless enc.ascii_compatible? if enc.dummy? origenc = enc enc = Encoding::Converter.asciicompat_encoding(enc) string = enc ? string.encode(enc) : string.b end string = string.gsub(Regexp.new('&(apos|amp|quot|gt|lt|#[0-9]|#x[0-9A-Fa-f]);'.encode(enc))) do case $1.encode(Encoding::US_ASCII) when 'apos' then "'".encode(enc) when 'amp' then '&'.encode(enc) when 'quot' then '"'.encode(enc) when 'gt' then '>'.encode(enc) when 'lt' then '<'.encode(enc) when /\A#0*(\d+)\z/ then $1.to_i.chr(enc) when /\A#x([0-9a-f]+)\z/i then $1.hex.chr(enc) end end string.encode!(origenc) if origenc return string end return string unless string.include? '&' charlimit = case enc when Encoding::UTF_8; 0x10ffff when Encoding::ISO_8859_1; 256 else 128 end string = string.b string.gsub!(/&(apos|amp|quot|gt|lt|\#[0-9]|\#[xX][0-9A-Fa-f]);/) do match = $1 case match when 'apos' then "'" when 'amp' then '&' when 'quot' then '"' when 'gt' then '>' when 'lt' then '<' else # Numeric character reference. Decode into the binary buffer so that a # non-ASCII byte already present in it never triggers an encoding # compatibility error on concatenation; the trailing force_encoding # re-tags the whole buffer. This mirrors the C extension's # optimized_unescape_html. n = match.start_with?('#x', '#X') ? match[2..-1].hex : match[1..-1].to_i if n >= charlimit "&#{match};" # out of range: keep the reference verbatim elsif charlimit > 256 [n].pack('U').b # UTF-8: code point bytes, surrogates included (like rb_enc_mbcput) else n.chr.b # ISO-8859-1 / ASCII: single byte end end end string.force_encoding enc end
#unescapeURIComponent(string, encoding = @@accept_charset) Also known as: #unescape_uri_component
URL-decode a string following RFC 3986 with encoding(optional). string = CGI.unescapeURIComponent("%27Stop%21%27+said%20Fred") # => "'Stop!'+said Fred"
# File 'lib/cgi/escape.rb', line 68
def unescapeURIComponent(string, encoding = @@accept_charset) str = string.b str.gsub!(/((?:%[0-9a-fA-F]{2})+)/) do |m| [m.delete('%')].pack('H*') end str.force_encoding(encoding) str.valid_encoding? ? str : str.force_encoding(string.encoding) end