Sets the ETag HTTP header based on the time stamps of the handler's file dependencies.
Assembly: System.Web (in System.Web.dll)
Public Sub SetETagFromFileDependencies
public void SetETagFromFileDependencies()
public: void SetETagFromFileDependencies()
member SetETagFromFileDependencies : unit -> unit
| Exception | Condition |
|---|---|
| InvalidOperationException |
The ETag header has already been set. |
The SetETagFromFileDependencies method sets the ETag header by retrieving the last modified time stamps of all files on which the handler is dependent, combining all file names and time stamps into a single string, then hashing that string into a single digest that is used as the ETag.
SetETagFromFileDependencies is introduced in the .NET Framework version 3.5. For more information, see .NET Framework Versions and Dependencies.
The following code example demonstrates how to set the ETag header.
Response.Cache.SetETagFromFileDependencies()
Response.Cache.SetETagFromFileDependencies();
.NET Framework
Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0Windows 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.