VaryByHeader Property

OutputCacheProfile.VaryByHeader Property

Updated: April 2009

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 = 

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

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

.NET Framework

Supported in: 3.5, 3.0, 2.0




April 2009

Changed comma-delimited to semicolon-delimited.

Content bug fix.

Community Additions

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