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case Element for filter for browserCaps (ASP.NET Settings Schema)

Allows pattern matching to stop after processing the first successful match out of a number of alternatives.


Using the browserCaps element in the Web.config file to define browsers is deprecated in the .NET Framework 2.0; however, it is still supported. The data in this element is merged with the information from the browser definition files (.browser) that are located in the machine-level %SystemRoot%\Microsoft.NET\Framework\version\CONFIG\Browsers folder and any existing application-level App_Browsers folders. For more information, see Browser Definition File Schema (browsers Element).

   match="regex expression"
   with="regex expression"
   [browser capability assignments, filter elements, case elements]

The following sections describe attributes, child elements, and parent elements.


Attribute Description


Required String attribute.

Specifies a .NET Framework regular expression that is tested against the with attribute. If omitted, the match is assumed successful.


Required String attribute.

Specifies the .NET Framework regular expression or string to search. If omitted, the string that is specified by the use element is used.

Child Elements


Parent Elements

Element Description


Specifies the required root element in every configuration file that is used by the common language runtime and the .NET Framework applications.


Specifies the root element for the ASP.NET configuration settings in a configuration file and contains configuration elements that configure ASP.NET Web applications and control how the applications behave.


Specifies the settings of supported browsers and the capabilities for the browsers. The browserCaps element can be updated as required to specify new browsers and capabilities.

For a list of valid browser properties, see HttpBrowserCapabilities.


Specifies a list of search strings that allow you to apply individual settings to specific browser definitions.

The case element allows pattern matching to stop after processing the first successful match out of a number of alternatives.

All filter and case elements can contain assignments and other filter and case elements. The difference between case and filter groups is this: after a filter group is evaluated, execution continues with the statement after the group, but after a case group is successfully matched and evaluated, execution skips to the end of the enclosing group.

In the .NET Framework version 2.0, the case element is not configured because the browserCaps element is deprecated in favor of using browser definition files to specify supported browsers and the capabilities for the browsers. For more information, see Browser Definition File Schema (browsers Element).

In the .NET Framework versions 1.0 and 1.1, the default case elements that are configured in the Machine.config file are too numerous to list here. For updates to the browser data go to Periodic device updates replace this browser capabilities section.

The following code example demonstrates how to parse the User-Agent HTTP header for any version of Microsoft Internet Explorer, as long as the format of the User-Agent string remains approximately unchanged.

The example makes use of the .NET Framework Regular Expressions and the ability of regular expressions to capture subexpressions in order to move version numbers directly from the User-Agent string to the browserCaps element.

The file specifies name/value pairs in the form of assignment statements, which is similar to Microsoft Internet Information Services (IIS) browscap.ini files. For example, the line "browser=IE" sets the value of the browser field to the string "IE".

      <result type="System.Web.HttpBrowserCapabilities, System.Web"/>
      <use var="HTTP_USER_AGENT"/>
         <case match="^Mozilla[^(]*\(compatible; MSIE 
            <case match="^2\." with="%{version}">
               <case match="2\.5b" with="%{version}">

Configuration section handler


Configuration member


Configurable locations


Root-level Web.config

Application-level Web.config

Virtual or physical directory–level Web.config


Microsoft Internet Information Services (IIS) version 5.0, 5.1, or 6.0

The .NET Framework version 2.0 (deprecated), 1.1, or 1.0

Microsoft Visual Studio 2003 or Visual Studio 2005