Returns the value of the named parameter in the URL or HTTP POST request.
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URL parameters passed into HTML form fields must be
entity encoded.
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Double quotes in URL parameters must be escaped when passed into other macros.
Example:
%SEARCH{ "%URLPARAM{ "search" encode="quote" }%" noheader="on" }%
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When used in a template topic, this macro will be expanded when the template is used to create a new topic. See
TemplateTopics#TemplateTopicsVars for details.
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Watch out for internal parameters, such as
rev
,
skin
,
template
,
topic
,
web
; they have a special meaning in Foswiki. Common parameters and view script specific parameters are documented at
CommandAndCGIScripts.
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If you have
%URLPARAM{
in the value of a URL parameter, it will be modified to
%<nop>URLPARAM{
. This is to prevent an infinite loop during expansion.
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Security warning! Using URLPARAM can easily be misused for cross-site scripting unless specific characters are entity encoded. By default URLPARAM encodes the characters
'"<>%
into HTML entities (same as encode="safe") which is relatively safe. The safest is to use encode="entity". When passing URLPARAM inside another macro always use double quotes ("") combined with using URLPARAM with encode="quote". For maximum security against cross-site scripting you are adviced to install the
Foswiki:Extensions.SafeWikiPlugin.