How do I get details of WCF bindings programatically

Question

I've written an ASP.Net web site with a WCF backend. One of the features of the web site is that it allows the user to download a file that is streamed from the WCF service.

The web.config file in the ASP.Net project has a maximum file size set in the binding (maxBufferSize and maxReceivedMessageSize). To stop users downloading files that exceed this size, I need to check the file size against the maximum file size in the web.config file, how do I go about this?

I've found out about the binding.CreateBindingElements() but I'm unsure how to get the instance of the binding in the first place.

EDIT: Binding details are as follows:

<binding name="BasicHttpBinding_IC_Server" closeTimeout="00:01:00"
      openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00"
      allowCookies="false" bypassProxyOnLocal="false" hostNameComparisonMode="StrongWildcard"
      maxBufferSize="65536" maxBufferPoolSize="524288" maxReceivedMessageSize="65536"
      messageEncoding="Text" textEncoding="utf-8" transferMode="Buffered"
      useDefaultWebProxy="true">

EDIT: The WCF service has a method that returns the file as a stream. An ASP.Net web page gets the file, stores it in a memory stream and then returns it as a byte array to the user.

If the file size is too small, I get this error:

The maximum message size quota for incoming messages (65536) has been exceeded. To increase the quota, use the MaxReceivedMessageSize property on the appropriate binding element.

Upping the buffer size fixes it, but I'd rather avoid this error by comparing the file size against the maxBufferSize.

Just to clarify, is your file actually "streamed" or just downloaded? In streaming, I believe the constraint settings are more around the size of the chunk rather than the file itself. Can you post your OperationContract definition? — Rich
Also, it sounds like you want the web site to access information about an endpoint exposed somewhere else in the app. This wouldn't be something where you're performing the check within the context of the WCF service itself, right? — Rich
@Rich - Thanks for your comments, I've added some detail to my post that should answer your questions. — GrandMasterFlush

GrandMasterFlush GrandMasterFlush · Accepted Answer · 2012-02-01T15:04:09

Finally managed to work it out myself.

Where sr is the service reference:

System.ServiceModel.Description.ServiceEndpoint endpoint = sr.Endpoint;
System.ServiceModel.Channels.BindingElementCollection elements =
    Endpoint.Binding.CreateBindingElements();
long size = elements.Find<System.ServiceModel.Channels.TransportBindingElement>().MaxReceivedMessageSize;

How do I get details of WCF bindings programatically

1 Answers