VarENCODE

ENCODE{"string"} -- encodes a string to HTML entities

  • Encode "special" characters to HTML numeric entities. Encoded characters are:
    • all non-printable ASCII characters below space, except newline ("\n") and linefeed ("\r")
    • HTML special characters "<", ">", "&", single quote (') and double quote (")
    • TWiki special characters "%", "[", "]", "@", "_", "*", "=" and "|"
  • Syntax: %ENCODE{"string"}%
  • Supported parameters:
    Parameter: Description: Default:
    "string" String to encode required (can be empty)
    type="url" Encode special characters for URL parameter use, like a double quote into %22 (this is the default)
    type="quotes" Escape double quotes with backslashes (\"), does not change other characters. This type does not protect against cross-site scripting. type="url"
    type="moderate" Encode special characters into HTML entities for moderate cross-site scripting protection: "<", ">", single quote (') and double quote (") are encoded. Useful to allow TWiki variables in comment boxes. type="url"
    type="safe" Encode special characters into HTML entities for cross-site scripting protection: "<", ">", "%", single quote (') and double quote (") are encoded. type="url"
    type="entity" Encode special characters into HTML entities, like a double quote into &#034;. Does not encode newline (\n) or linefeed (\r). type="url"
    type="html" Encode special characters into HTML entities. In addition to type="entity", it also encodes space, \n and \r. Useful to encode text properly in HTML input fields. type="url"
  • Example: %ENCODE{"spaced name"}% expands to spaced%20name
  • ALERT! Notes:
    • Values of HTML input fields should encoded as "html".
      Example: <input type="text" name="address" value="%ENCODE{ "any text" type="html" }%" />
    • Double quotes in strings must be escaped when passed into other TWiki variables.
      Example: %SEARCH{ "%ENCODE{ "string with "quotes"" type="quotes" }%" noheader="on" }%
    • Use type="moderate", type="safe" or type="entity" to protect user input from URL parameters and external sources against cross-site scripting (XSS). type="entity" is the safest mode, but some TWiki applications might not work. type="safe" provides a safe middle ground, type="moderate" provides only moderate cross-site scripting protection.