HttpCachePolicy.SetETag(String) Method
Definition
Important
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Sets the ETag HTTP header to the specified string.
public:
void SetETag(System::String ^ etag);public void SetETag (string etag);member this.SetETag : string -> unitPublic Sub SetETag (etag As String)Parameters
- etag
- String
The text to use for the ETag header.
Exceptions
etag is null.
The ETag header has already been set.
-or-
The SetETagFromFileDependencies() has already been called.
Examples
The following code example demonstrates how to set the ETag header to a custom value.
Response.Cache.SetETag("\"50f59e42f4d8bc1:cd7\"");
Response.Cache.SetETag("""50f59e42f4d8bc1:cd7""")
Remarks
The ETag header is a unique identifier for a specific version of a document. It is used by clients to validate client-cached content to avoid requesting it again. Once an ETag header is set, subsequent attempts to set it fail and an exception is thrown.
SetETag is introduced in the .NET Framework version 3.5. For more information, see Versions and Dependencies.
