VarENCODE - System

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 (")
- TML special characters "%", "[", "]", "@", "_", "*", "=" and "|"
Syntax: %ENCODE{"string"}%

Supported parameters:

Parameter:	Description:	Default:
`"string"`	String to encode	required (can be empty)
`type="entity"` `type="safe"` `type="html"` `type="quotes"` `type="url"`	Control how special characters are encoded `entity`: Encode special characters into HTML entities, like a double quote into `"`. Does not encode `\n` or `\r`. `safe`: Encode characters `'"<>%` into HTML entities. `html`: As `type="entity"` except it also encodes `\n` and `\r` `quotes`: Escape double quotes with backslashes (`\"`), does not change other characters `url`: Encode special characters for URL parameter use, like a double quote into `%22` (this is the default)	`type="url"`

Example: %ENCODE{"spaced name"}% expands to spaced%20name
Values of HTML input fields must be entity encoded.
Example: <input type="text" name="address" value="%ENCODE{ "any text" type="entity" }%" />
Double quotes in strings must be escaped when passed into other macros.
Example: %SEARCH{ "%ENCODE{ "string with "quotes"" type="quotes" }%" noheader="on" }%
ENCODE can be used to filter user input from URL parameters and similer to protect against cross-site scripting. The safest approach is to use type="entity". This can however prevent an application from fully working. You can then use type="safe" which encodes only the characters '"<>% into HTML entities (same as encode="safe"). When ENCODE is passing a string inside another macro always use double quotes ("") type="quote". For maximum security against cross-site scripting you are adviced to install the Foswiki:Extensions.SafeWikiPlugin.