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OutputCacheProfile.VaryByHeader Property

Gets or sets the VaryByHeader property.

Namespace:  System.Web.Configuration
Assembly:  System.Web (in System.Web.dll)

public string VaryByHeader { get; set; }

Property Value

Type: System.String
The VaryByHeader value.

The VaryByHeader is a semicolon-delimited set of headers used to vary the cached output. These are HTTP headers associated with the request. For more information, see Caching Multiple Versions of a Page.


The VaryByHeader settings are the same ones used by the VaryByHeader attribute of the @ OutputCache. Varying by all headers by setting the value of "*" is not recommended. It can result in cache overflow or a denial of service attack on the Web server.

The following code example shows how to use the VaryByHeader property.

      // Get the current VaryByHeader.
      String varyByHeaderValue = 

      // Set the VaryByHeader.
      outputCacheProfile.VaryByHeader = 

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.