How to catch ConfigurationErrorsException for violating maxRequestLength?

Question

I am limiting file size users can upload to the site from Web.config. As explained here, it should throw a ConfigurationErrorsException if size is not accepted. I tried to c

Answer 1

   catch (Exception ex)
   {
       if (ex is HttpException && (ex as HttpException).WebEventCode == 3004)
       {
            //-- you can now inform the client that file uploaded was too large.
       }
       else
           throw;
   }

Answer 2

There is no way to do it right without a client-side help. You cannot determine if the request is too long unless you read all of it. If you read each request to the end, anyone come and keep your server busy. If you just look at content length and drop the request, other side is going to think there is a connection problem. It's nothing you can do with error handling, it's a shortcoming of HTTP.

You can use Flash or Javascript components to make it right because this thing can't fail nicely.

Answer 3

I am not 100% on this, but I think it might help if you tried changing:

context.Response.Redirect(this.Request.Url.LocalPath + "?action=exception");

to

Server.Transfer(this.Request.Url.LocalPath + "?action=exception,false)

My thinking is that the the over-max-request-length Request is still being processed in the Redirect call but if you tell it to ditch the form data, it will become under the max request length and then it might behave differently.

No guarantees, but its easy to check.

Answer 4

I have a similar issue in that I want to catch the 'Maximum request length exceeded' exception within the Application_Error handler and then do a Redirect.

(The difference is that I am writing a REST service with ASP.Net Web API and instead of redirecting to an error page, I wanted to redirect to an Error controller which would then return the appropriate response).

However, what I found was that when running the application through the ASP.Net Development Server, the Response.Redirect didn't seem to be working. Fiddler would state "ReadResponse() failed: The server did not return a response for this request."

My client (Advanced REST Client for Chrome) would simply show "0 NO RESPONSE".

If I then ran the application via a local copy of IIS on my development machine then the redirect would work correctly!

I'm not sure i can definitively say that Response.Redirect does not work on the ASP.Net Development Server but it certainly wasn't working in my situation.

So, I recommend trying to run your application through IIS instead of IIS Express or the Development Server and see if you get a different result.

See this link on how to Specify the Web Server for Web Projects in Visual Studio:

http://msdn.microsoft.com/en-us/library/ms178108(v=vs.100).aspx

Answer 5

You cant catch error in action method becouse exception comes earlier, but you can catch it here

protected void Application_Error() {
     var lastError = Server.GetLastError();
     if(lastError !=null && lastError is HttpException && lastError.Message.Contains("exceed")) {
      Response.Redirect("~/errors/RequestLengthExceeded");
      }
    }   

Actualy when file size exceeds limits HttpException error arise.

There is also IIS limit on content - wich can't be catched in application. IIS 7 throws

HTTP Error 404.13 - Not Found The request filtering module is configured to deny a request that exceeds the request content length.

You can google it, there is a lot of information about this iis error.