ASP.NET MVC Response Filter + OutputCache Attribute
- by Shane Andrade
I'm not sure if this is an ASP.NET MVC specific thing or ASP.NET in general but here's what's happening. I have an action filter that removes whitespace by the use of a response filter:
public class StripWhitespaceAttribute : ActionFilterAttribute
{
public StripWhitespaceAttribute ()
{
}
public override void OnResultExecuted(ResultExecutedContext filterContext)
{
base.OnResultExecuted(filterContext);
filterContext.HttpContext.Response.Filter = new WhitespaceFilter(filterContext.HttpContext.Response.Filter);
}
}
When used in conjunction with the OutputCache attribute, my calls to Response.WriteSubstitution for "donut hole caching" do not work. The first and second time the page loads the callback passed to WriteSubstitution get called, after that they are not called anymore until the output cache expires. I've noticed this with not just this particular filter but any filter used on Response.Filter... am I missing something?
I also forgot to mention I've tried this without the use of an MVC action filter attribute by attaching to the PostReleaseRequestState event in the global.asax and setting the Response.Filter value there... but still no luck.
