HttpCachePolicy.SetOmitVaryStar Method (Boolean)
Specifies whether the response should contain the vary:* header when varying by parameters.
Assembly: System.Web (in System.Web.dll)
This method allows you to prevent the output ached from adding a vary:* header to the outgoing response when the cached response varies by parameter. This is useful for clients varying caching by query string because most clients will automatically vary by query string without requiring the vary:* header.
The use of the vary:* header can disable all client caching.
Available since 2.0