HttpCacheVaryByHeaders.xml

<Type Name="HttpCacheVaryByHeaders" FullName="System.Web.HttpCacheVaryByHeaders">
  <TypeSignature Language="C#" Value="public sealed class HttpCacheVaryByHeaders" />
  <TypeSignature Language="ILAsm" Value=".class public auto ansi sealed beforefieldinit HttpCacheVaryByHeaders extends System.Object" />
  <TypeSignature Language="DocId" Value="T:System.Web.HttpCacheVaryByHeaders" />
  <TypeSignature Language="VB.NET" Value="Public NotInheritable Class HttpCacheVaryByHeaders" />
  <TypeSignature Language="F#" Value="type HttpCacheVaryByHeaders = class" />
  <TypeSignature Language="C++ CLI" Value="public ref class HttpCacheVaryByHeaders sealed" />
  <AssemblyInfo>
    <AssemblyName>System.Web</AssemblyName>
    <AssemblyVersion>1.0.5000.0</AssemblyVersion>
    <AssemblyVersion>2.0.0.0</AssemblyVersion>
    <AssemblyVersion>4.0.0.0</AssemblyVersion>
  </AssemblyInfo>
  <Base>
    <BaseTypeName>System.Object</BaseTypeName>
  </Base>
  <Interfaces />
  <Docs>
    <summary>Provides a type-safe way to set the <see cref="P:System.Web.HttpCachePolicy.VaryByHeaders" /> property.</summary>
    <remarks>
      <format type="text/markdown"><![CDATA[  
  
## Remarks  
 The <xref:System.Web.HttpCachePolicy.VaryByHeaders> property identifies which request headers ASP.NET uses to uniquely identify a variation of the response when there are multiple cached responses for a resource. This is useful when a response depends on a set of request headers. In this way, `VaryByHeaders` lets the output cache store and serve the appropriate representation of a resource for a given request.  
  
> [!IMPORTANT]
> Output caching is a performance optimization feature. The `VaryBy` settings are designed to cache alternate representations of a resource based on request characteristics; they are not designed to isolate audiences or classes of content. Do not rely on cache variation to separate personalized, tenant-specific, authorization-dependent, or otherwise sensitive responses. Enforce any required isolation between request contexts independently of the cache configuration.
  
 The <xref:System.Web.HttpCacheVaryByHeaders> is not directly related to HTTP cache-control headers, but helps ensure that a client or proxy varies by the specified headers. For more information about `VaryByHeaders`, see RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1, available on the [World Wide Web Consortium (W3C) Web site](https://go.microsoft.com/fwlink/?linkid=37125). See section 14, "Header Field Definitions", for complete details.  
  
 ]]></format>
    </remarks>
    <altmember cref="T:System.Web.HttpCacheVaryByParams" />
    <related type="Article" href="https://learn.microsoft.com/previous-versions/aspnet/xadzbzd6(v=vs.100)">Caching Multiple Versions of a Page</related>
    <related type="Article" href="https://learn.microsoft.com/previous-versions/aspnet/a6s4ks5w(v=vs.100)">How to: Cache Versions of a Page, Based on HTTP Headers</related>
  </Docs>
  <Members>
    <Member MemberName=".ctor">
      <MemberSignature Language="C#" Value="public HttpCacheVaryByHeaders ();" FrameworkAlternate="netframework-4.0;netframework-4.5;netframework-4.5.1;netframework-4.5.2;netframework-4.6;netframework-4.6.1;netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberSignature Language="ILAsm" Value=".method public hidebysig specialname rtspecialname instance void .ctor() cil managed" FrameworkAlternate="netframework-4.0;netframework-4.5;netframework-4.5.1;netframework-4.5.2;netframework-4.6;netframework-4.6.1;netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberSignature Language="DocId" Value="M:System.Web.HttpCacheVaryByHeaders.#ctor" FrameworkAlternate="netframework-4.0;netframework-4.5;netframework-4.5.1;netframework-4.5.2;netframework-4.6;netframework-4.6.1;netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberSignature Language="VB.NET" Value="Public Sub New ()" FrameworkAlternate="netframework-4.0;netframework-4.5;netframework-4.5.1;netframework-4.5.2;netframework-4.6;netframework-4.6.1;netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberSignature Language="C++ CLI" Value="public:&#xA; HttpCacheVaryByHeaders();" FrameworkAlternate="netframework-4.0;netframework-4.5;netframework-4.5.1;netframework-4.5.2;netframework-4.6;netframework-4.6.1;netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberType>Constructor</MemberType>
      <AssemblyInfo>
        <AssemblyName>System.Web</AssemblyName>
        <AssemblyVersion>4.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <Parameters />
      <Docs>
        <summary>Initializes a new instance of the <see cref="T:System.Web.HttpCacheVaryByHeaders" /> class.</summary>
        <remarks>To be added.</remarks>
      </Docs>
    </Member>
    <Member MemberName="AcceptTypes">
      <MemberSignature Language="C#" Value="public bool AcceptTypes { get; set; }" />
      <MemberSignature Language="ILAsm" Value=".property instance bool AcceptTypes" />
      <MemberSignature Language="DocId" Value="P:System.Web.HttpCacheVaryByHeaders.AcceptTypes" />
      <MemberSignature Language="VB.NET" Value="Public Property AcceptTypes As Boolean" />
      <MemberSignature Language="F#" Value="member this.AcceptTypes : bool with get, set" Usage="System.Web.HttpCacheVaryByHeaders.AcceptTypes" />
      <MemberSignature Language="C++ CLI" Value="public:&#xA; property bool AcceptTypes { bool get(); void set(bool value); };" />
      <MemberType>Property</MemberType>
      <AssemblyInfo>
        <AssemblyName>System.Web</AssemblyName>
        <AssemblyVersion>1.0.5000.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
        <AssemblyVersion>4.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <Attributes>
        <Attribute FrameworkAlternate="netframework-4.0">
          <AttributeName Language="C#">[get: System.Runtime.TargetedPatchingOptOut("Performance critical to inline this type of method across NGen image boundaries")]</AttributeName>
          <AttributeName Language="F#">[&lt;get: System.Runtime.TargetedPatchingOptOut("Performance critical to inline this type of method across NGen image boundaries")&gt;]</AttributeName>
        </Attribute>
      </Attributes>
      <ReturnValue>
        <ReturnType>System.Boolean</ReturnType>
      </ReturnValue>
      <Docs>
        <summary>Gets or sets a value indicating whether the ASP.NET output cache varies the cached responses by the <see langword="Accept" /> HTTP header, and appends it to the out-going <see langword="Vary" /> HTTP header.</summary>
        <value>
          <see langword="true" /> when the ASP.NET output cache varies by the <see langword="Accept" /> header; otherwise, <see langword="false" />. The default value is <see langword="false" />.</value>
        <remarks>
          <format type="text/markdown"><![CDATA[  
  
## Remarks  
 The `Vary` header indicates the request-header fields that the server varies the response by the `Accept` field and specifies that the server selects the response based on the media types acceptable to the client.  
  
 For more information on HTTP headers, see RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1, available on the [World Wide Web Consortium (W3C) Web site](https://go.microsoft.com/fwlink/?linkid=37125). See section 14, "Header Field Definitions", for complete details.  
  
   
  
## Examples  
 This following code example demonstrates how some action is performed only if the <xref:System.Web.HttpCacheVaryByHeaders.AcceptTypes%2A> property is `true`.  
  
 [!code-csharp[Classic HttpCacheVaryByHeaders.AcceptTypes Example#1](~/snippets/csharp/VS_Snippets_WebNet/Classic HttpCacheVaryByHeaders.AcceptTypes Example/cs/source.aspx#1)]
 [!code-vb[Classic HttpCacheVaryByHeaders.AcceptTypes Example#1](~/snippets/visualbasic/VS_Snippets_WebNet/Classic HttpCacheVaryByHeaders.AcceptTypes Example/vb/source.aspx#1)]  
  
 ]]></format>
        </remarks>
      </Docs>
    </Member>
    <Member MemberName="GetHeaders">
      <MemberSignature Language="C#" Value="public string[] GetHeaders ();" FrameworkAlternate="netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberSignature Language="ILAsm" Value=".method public hidebysig instance string[] GetHeaders() cil managed" FrameworkAlternate="netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberSignature Language="DocId" Value="M:System.Web.HttpCacheVaryByHeaders.GetHeaders" FrameworkAlternate="netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberSignature Language="VB.NET" Value="Public Function GetHeaders () As String()" FrameworkAlternate="netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberSignature Language="C++ CLI" Value="public:&#xA; cli::array &lt;System::String ^&gt; ^ GetHeaders();" FrameworkAlternate="netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberSignature Language="F#" Value="member this.GetHeaders : unit -&gt; string[]" Usage="httpCacheVaryByHeaders.GetHeaders " FrameworkAlternate="netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      <MemberType>Method</MemberType>
      <AssemblyInfo>
        <AssemblyName>System.Web</AssemblyName>
        <AssemblyVersion>4.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <ReturnValue>
        <ReturnType FrameworkAlternate="netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1">System.String[]</ReturnType>
      </ReturnValue>
      <Parameters />
      <Docs>
        <summary>Gets an array of values which specify the HTTP headers to be used for varying the cache.</summary>
        <returns>An array of values which contain the HTTP headers for varying the cache.</returns>
        <remarks>To be added.</remarks>
      </Docs>
    </Member>
    <Member MemberName="Item">
      <MemberSignature Language="C#" Value="public bool this[string header] { get; set; }" />
      <MemberSignature Language="ILAsm" Value=".property instance bool Item(string)" />
      <MemberSignature Language="DocId" Value="P:System.Web.HttpCacheVaryByHeaders.Item(System.String)" />
      <MemberSignature Language="VB.NET" Value="Default Public Property Item(header As String) As Boolean" />
      <MemberSignature Language="F#" Value="member this.Item(string) : bool with get, set" Usage="System.Web.HttpCacheVaryByHeaders.Item" />
      <MemberSignature Language="C++ CLI" Value="public:&#xA; property bool default[System::String ^] { bool get(System::String ^ header); void set(System::String ^ header, bool value); };" />
      <MemberType>Property</MemberType>
      <AssemblyInfo>
        <AssemblyName>System.Web</AssemblyName>
        <AssemblyVersion>1.0.5000.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
        <AssemblyVersion>4.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <ReturnValue>
        <ReturnType>System.Boolean</ReturnType>
      </ReturnValue>
      <Parameters>
        <Parameter Name="header" Type="System.String" />
      </Parameters>
      <Docs>
        <param name="header">The name of the custom header.</param>
        <summary>Gets or sets a custom header field that the ASP.NET output cache varies the cached responses by, and appends it to the out-going <see langword="Vary" /> HTTP header.</summary>
        <value>
          <see langword="true" /> when the ASP.NET output cache varies by the specified custom field; otherwise, <see langword="false" />. The default value is <see langword="false" />.</value>
        <remarks>
          <format type="text/markdown"><![CDATA[  
  
## Remarks  
 The `Vary` header indicates the request-header fields that the server varies the response by.  
  
 For more information, see RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1, available on the [World Wide Web Consortium (W3C) Web site](https://go.microsoft.com/fwlink/?linkid=37125). See section 14, "Header Field Definitions", for complete details.  
  
 The <xref:System.Web.HttpCacheVaryByHeaders.VaryByUnspecifiedParameters%2A> method is called internally if the specified `header` has the value * (an asterisk).  
  
 ]]></format>
        </remarks>
        <exception cref="T:System.ArgumentNullException">
          <paramref name="header" /> is <see langword="null" />.</exception>
        <related type="Article" href="https://learn.microsoft.com/previous-versions/aspnet/xadzbzd6(v=vs.100)">Caching Multiple Versions of a Page</related>
        <related type="Article" href="https://learn.microsoft.com/previous-versions/aspnet/a6s4ks5w(v=vs.100)">How to: Cache Versions of a Page, Based on HTTP Headers</related>
      </Docs>
    </Member>
    <Member MemberName="SetHeaders">
      <MemberSignature Language="C#" Value="public void SetHeaders (string[] headers);" />
      <MemberSignature Language="ILAsm" Value=".method public hidebysig instance void SetHeaders(string[] headers) cil managed" />
      <MemberSignature Language="DocId" Value="M:System.Web.HttpCacheVaryByHeaders.SetHeaders(System.String[])" />
      <MemberSignature Language="VB.NET" Value="Public Sub SetHeaders (headers As String())" />
      <MemberSignature Language="F#" Value="member this.SetHeaders : string[] -&gt; unit" Usage="httpCacheVaryByHeaders.SetHeaders headers" />
      <MemberSignature Language="C++ CLI" Value="public:&#xA; void SetHeaders(cli::array &lt;System::String ^&gt; ^ headers);" />
      <MemberType>Method</MemberType>
      <AssemblyInfo>
        <AssemblyName>System.Web</AssemblyName>
        <AssemblyVersion>4.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <ReturnValue>
        <ReturnType>System.Void</ReturnType>
      </ReturnValue>
      <Parameters>
        <Parameter Name="headers" Type="System.String[]" Index="0" FrameworkAlternate="netframework-4.6.2;netframework-4.7;netframework-4.7.1;netframework-4.7.2;netframework-4.8;netframework-4.8.1" />
      </Parameters>
      <Docs>
        <param name="headers">An array of values which contain the HTTP headers for varying the cache.</param>
        <summary>Sets an array of values which specify the HTTP headers to be used for varying the cache.</summary>
        <remarks>To be added.</remarks>
      </Docs>
    </Member>
    <Member MemberName="UserAgent">
      <MemberSignature Language="C#" Value="public bool UserAgent { get; set; }" />
      <MemberSignature Language="ILAsm" Value=".property instance bool UserAgent" />
      <MemberSignature Language="DocId" Value="P:System.Web.HttpCacheVaryByHeaders.UserAgent" />
      <MemberSignature Language="VB.NET" Value="Public Property UserAgent As Boolean" />
      <MemberSignature Language="F#" Value="member this.UserAgent : bool with get, set" Usage="System.Web.HttpCacheVaryByHeaders.UserAgent" />
      <MemberSignature Language="C++ CLI" Value="public:&#xA; property bool UserAgent { bool get(); void set(bool value); };" />
      <MemberType>Property</MemberType>
      <AssemblyInfo>
        <AssemblyName>System.Web</AssemblyName>
        <AssemblyVersion>1.0.5000.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
        <AssemblyVersion>4.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <Attributes>
        <Attribute FrameworkAlternate="netframework-4.0">
          <AttributeName Language="C#">[get: System.Runtime.TargetedPatchingOptOut("Performance critical to inline this type of method across NGen image boundaries")]</AttributeName>
          <AttributeName Language="F#">[&lt;get: System.Runtime.TargetedPatchingOptOut("Performance critical to inline this type of method across NGen image boundaries")&gt;]</AttributeName>
        </Attribute>
      </Attributes>
      <ReturnValue>
        <ReturnType>System.Boolean</ReturnType>
      </ReturnValue>
      <Docs>
        <summary>Gets or sets a value indicating whether the ASP.NET output cache varies the cached responses by the <see langword="User-Agent" /> header, and appends it to the out-going <see langword="Vary" /> HTTP header.</summary>
        <value>
          <see langword="true" /> when the ASP.NET output cache varies by the <see langword="User-Agent" /> header, and adds it to the <see langword="Vary" /> HTTP header sent to the client; otherwise, <see langword="false" />. The default value is <see langword="false" />.</value>
        <remarks>
          <format type="text/markdown"><![CDATA[  
  
## Remarks  
 The `Vary` header indicates the request-header fields that the server uses to determine which of multiple cached responses is sent in response to a client request. The `User-Agent` field specifies that the server selects the response based on the client's user-agent type.  
  
 For more information, see RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1, available on the [World Wide Web Consortium (W3C) Web site](https://go.microsoft.com/fwlink/?linkid=37125). See section 14, "Header Field Definitions", for complete details.  
  
   
  
## Examples  
 The following code example demonstrates how some action is performed only if the <xref:System.Web.HttpCacheVaryByHeaders.UserAgent%2A> property is `true`.  
  
 [!code-csharp[Classic HttpCacheVaryByHeaders.UserAgent Example#1](~/snippets/csharp/VS_Snippets_WebNet/Classic HttpCacheVaryByHeaders.UserAgent Example/cs/source.aspx#1)]
 [!code-vb[Classic HttpCacheVaryByHeaders.UserAgent Example#1](~/snippets/visualbasic/VS_Snippets_WebNet/Classic HttpCacheVaryByHeaders.UserAgent Example/vb/source.aspx#1)]  
  
 ]]></format>
        </remarks>
      </Docs>
    </Member>
    <Member MemberName="UserCharSet">
      <MemberSignature Language="C#" Value="public bool UserCharSet { get; set; }" />
      <MemberSignature Language="ILAsm" Value=".property instance bool UserCharSet" />
      <MemberSignature Language="DocId" Value="P:System.Web.HttpCacheVaryByHeaders.UserCharSet" />
      <MemberSignature Language="VB.NET" Value="Public Property UserCharSet As Boolean" />
      <MemberSignature Language="F#" Value="member this.UserCharSet : bool with get, set" Usage="System.Web.HttpCacheVaryByHeaders.UserCharSet" />
      <MemberSignature Language="C++ CLI" Value="public:&#xA; property bool UserCharSet { bool get(); void set(bool value); };" />
      <MemberType>Property</MemberType>
      <AssemblyInfo>
        <AssemblyName>System.Web</AssemblyName>
        <AssemblyVersion>1.0.5000.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
        <AssemblyVersion>4.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <Attributes>
        <Attribute FrameworkAlternate="netframework-4.0">
          <AttributeName Language="C#">[get: System.Runtime.TargetedPatchingOptOut("Performance critical to inline this type of method across NGen image boundaries")]</AttributeName>
          <AttributeName Language="F#">[&lt;get: System.Runtime.TargetedPatchingOptOut("Performance critical to inline this type of method across NGen image boundaries")&gt;]</AttributeName>
        </Attribute>
      </Attributes>
      <ReturnValue>
        <ReturnType>System.Boolean</ReturnType>
      </ReturnValue>
      <Docs>
        <summary>Gets or sets a value indicating whether the ASP.NET output cache varies the cached responses by the <see langword="Accept-Charset" /> header, and appends it to the out-going <see langword="Vary" /> HTTP header.</summary>
        <value>
          <see langword="true" /> when the ASP.NET output cache varies by the <see langword="Accept-Charset" /> header and adds it to the <see langword="Vary" /> HTTP header sent to the client; otherwise, <see langword="false" />. The default value is <see langword="false" />.</value>
        <remarks>
          <format type="text/markdown"><![CDATA[  
  
## Remarks  
 The `Vary` header indicates the request-header fields that the server uses to determine which of multiple cached responses is sent in response to a client request. The `Accept-CharSet` field specifies that the server selects the response based on the client's character set.  
  
 For more information, see RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1, available on the [World Wide Web Consortium (W3C) Web site](https://go.microsoft.com/fwlink/?linkid=37125). See section 14, "Header Field Definitions", for complete details.  
  
   
  
## Examples  
 The following code example demonstrates how some action is performed only if the <xref:System.Web.HttpCacheVaryByHeaders.UserCharSet%2A> property is `true`.  
  
 [!code-csharp[Classic HttpCacheVaryByHeaders.UserCharSet Example#1](~/snippets/csharp/VS_Snippets_WebNet/Classic HttpCacheVaryByHeaders.UserCharSet Example/cs/source.aspx#1)]
 [!code-vb[Classic HttpCacheVaryByHeaders.UserCharSet Example#1](~/snippets/visualbasic/VS_Snippets_WebNet/Classic HttpCacheVaryByHeaders.UserCharSet Example/vb/source.aspx#1)]  
  
 ]]></format>
        </remarks>
      </Docs>
    </Member>
    <Member MemberName="UserLanguage">
      <MemberSignature Language="C#" Value="public bool UserLanguage { get; set; }" />
      <MemberSignature Language="ILAsm" Value=".property instance bool UserLanguage" />
      <MemberSignature Language="DocId" Value="P:System.Web.HttpCacheVaryByHeaders.UserLanguage" />
      <MemberSignature Language="VB.NET" Value="Public Property UserLanguage As Boolean" />
      <MemberSignature Language="F#" Value="member this.UserLanguage : bool with get, set" Usage="System.Web.HttpCacheVaryByHeaders.UserLanguage" />
      <MemberSignature Language="C++ CLI" Value="public:&#xA; property bool UserLanguage { bool get(); void set(bool value); };" />
      <MemberType>Property</MemberType>
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        <AssemblyName>System.Web</AssemblyName>
        <AssemblyVersion>1.0.5000.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
        <AssemblyVersion>4.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <Attributes>
        <Attribute FrameworkAlternate="netframework-4.0">
          <AttributeName Language="C#">[get: System.Runtime.TargetedPatchingOptOut("Performance critical to inline this type of method across NGen image boundaries")]</AttributeName>
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      <ReturnValue>
        <ReturnType>System.Boolean</ReturnType>
      </ReturnValue>
      <Docs>
        <summary>Gets or sets a value indicating whether the ASP.NET output cache varies the cached responses by the <see langword="Accept-Language" /> header, and appends it to the out-going <see langword="Vary" /> HTTP header.</summary>
        <value>
          <see langword="true" /> when ASP.NET output cache varies by the <see langword="Accept-Language" /> header and adds it to the <see langword="Vary" /> HTTP header sent to the client; otherwise, <see langword="false" />. The default value is <see langword="false" />.</value>
        <remarks>
          <format type="text/markdown"><![CDATA[  
  
## Remarks  
 The `Vary` header indicates the request-header fields that the server uses to determine which of multiple cached responses is sent in response to a client request. The `Accept-Language` field specifies that the server selects the response based on languages acceptable to the client.  
  
 For more information, see RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1, available on the [World Wide Web Consortium (W3C) Web site](https://go.microsoft.com/fwlink/?linkid=37125). See section 14, "Header Field Definitions", for complete details.  
  
   
  
## Examples  
 The following code example demonstrates how some action is performed only if the <xref:System.Web.HttpCacheVaryByHeaders.UserLanguage%2A> property is `true`.  
  
 [!code-csharp[Classic HttpCacheVaryByHeaders.UserLanguage Example#1](~/snippets/csharp/VS_Snippets_WebNet/Classic HttpCacheVaryByHeaders.UserLanguage Example/cs/source.aspx#1)]
 [!code-vb[Classic HttpCacheVaryByHeaders.UserLanguage Example#1](~/snippets/visualbasic/VS_Snippets_WebNet/Classic HttpCacheVaryByHeaders.UserLanguage Example/vb/source.aspx#1)]  
  
 ]]></format>
        </remarks>
      </Docs>
    </Member>
    <Member MemberName="VaryByUnspecifiedParameters">
      <MemberSignature Language="C#" Value="public void VaryByUnspecifiedParameters ();" />
      <MemberSignature Language="ILAsm" Value=".method public hidebysig instance void VaryByUnspecifiedParameters() cil managed" />
      <MemberSignature Language="DocId" Value="M:System.Web.HttpCacheVaryByHeaders.VaryByUnspecifiedParameters" />
      <MemberSignature Language="VB.NET" Value="Public Sub VaryByUnspecifiedParameters ()" />
      <MemberSignature Language="F#" Value="member this.VaryByUnspecifiedParameters : unit -&gt; unit" Usage="httpCacheVaryByHeaders.VaryByUnspecifiedParameters " />
      <MemberSignature Language="C++ CLI" Value="public:&#xA; void VaryByUnspecifiedParameters();" />
      <MemberType>Method</MemberType>
      <AssemblyInfo>
        <AssemblyName>System.Web</AssemblyName>
        <AssemblyVersion>1.0.5000.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
        <AssemblyVersion>4.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <ReturnValue>
        <ReturnType>System.Void</ReturnType>
      </ReturnValue>
      <Parameters />
      <Docs>
        <summary>Causes ASP.NET to vary by all header values and sets the <see langword="Vary" /> HTTP header to the value * (an asterisk). All other <see langword="Vary" /> header information to be dropped.</summary>
        <remarks>
          <format type="text/markdown"><![CDATA[  
  
## Remarks  
 The `Vary` header indicates the request-header fields that the server uses to determine which of multiple cached responses is sent in response to a client request. The * value specifies that the server selects the response based on parameters not specified in request headers (for example, the network address of the client).  
  
 For more information, see RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1, available on the [World Wide Web Consortium (W3C) Web site](https://go.microsoft.com/fwlink/?linkid=37125). See section 14, "Header Field Definitions", for complete details.  
  
 ]]></format>
        </remarks>
      </Docs>
    </Member>
  </Members>
</Type>