Inherited WebServiceAttribute from WebService-derived Base Class not showing on asmx page

Question

I have a library project that includes a standard web service base class. I then inherit that base class for the specific websites that implement the web service.

Here is a simplified example:

[WebService(
     Namespace = "http://CanI.InheritThis.com/",
     Name = "WebServiceBaseClass",
     Description = "This Webservice is overloaded on specific websites")]
public abstract class CustomWebServiceBase : WebService
{
    //shared web service guts
}

public class MyService : CustomWebServiceBase
{
     //overloaded items
}

When I open up myservice.asmx it still says I'm using the default namespace (http://tempuri.org). How do I get the webservice to show the inherited namespace(http://CanI.InheritThis.com/)?

Update: I attempted to create a custom attribute that inherits from the WebServiceAttribute class but found that WebServiceAttribute is sealed.

Is there a way to add Inherited = true to WebServiceAttribute?

Update 2: Even more confusing I followed J0e3gan's advice and created the following in linqpad (with the System.Web.Services.dll added and namespace added.

void Main()
{
    Console.WriteLine(typeof(MyService).GetCustomAttributes().First());
}
[WebService(
     Namespace = "http://CanI.InheritThis.com/",
     Name = "WebServiceBaseClass",
     Description = "This Webservice is overloaded on specific websites")]
public abstract class CustomWebServiceBase : WebService
{
    //shared web service guts
}

public class MyService : CustomWebServiceBase
{
     //overloaded items
}

Which says it's getting the correct attribute, however the asmx page still claims to be using the default namespace.

Update 3: restarted from scratch, checked into bitbucket, same issue Update 4: As @J0e3gan pointed out, the bitbucket project was missing the class library, I've fixed that.

Answer 1

Initial Answer

WebServiceAttribute already supports its inheritance by subclasses of classes to which it is applied.

Maybe you just need to rebuild your library and service projects? A related SO question outlines some other possibilities that may explain why browsing to your service still shows the default namespace http://tempuri.org/.

See the following LINQPad 4 program (with System.Web.Services.dll referenced and the System.Web.Services namespace imported) for an example of WebServiceAttribute applied to a base class with subclasses inheriting and overriding the attribute:

void Main()
{
    Console.WriteLine(typeof(CustomWebServiceBase).GetCustomAttributes().First());
    Console.WriteLine(typeof(SomeSiteService).GetCustomAttributes().First());
    Console.WriteLine(typeof(AnotherSiteService).GetCustomAttributes().First());
}

[WebService(
     Namespace = "http://CanI.InheritThis.com/",
     Name = "WebServiceBaseClass",
     Description = "This Webservice is overloaded on specific websites")]
public class CustomWebServiceBase : WebService
{
}

public class SomeSiteService : CustomWebServiceBase
{
}

[WebService(
     Namespace = "http://YesU.Can.AndOverride.it/",
     Name = "WebServiceDerivedClass",
     Description = "This Webservice is for a specific website")]
public class AnotherSiteService : CustomWebServiceBase
{
}

It yields the following output:

Follow-Up to Bitbucket Solution

Looking at the Bitbucket solution that displays the issue, I was able to reproduce it by building and running it as-is:

To fix the issue, I simply decorated MyService with WebServiceAttribute (in the MyServiceWebApp project's MyService.asmx.cs) as follows:

// NOTE: necessary using directive - requiring a corresponding reference to
// System.Web.Services.dll
using System.Web.Services;

namespace MyServiceWebApp
{
    // NOTE: the key - the overriding decoration of the derived web-service
    // class with WebServiceAttribute
    [WebService(
     Namespace = "http://YesU.Can.AndOverride.it/",
     Name = "WebServiceDerivedClass",
     Description = "This Webservice is for a specific website")]
    public class MyService : WebServiceClassLibrary.CustomWebServiceBase
    {

    }
}

Here are screenshots of the fix's results:

You can clearly see that MyService.asmx no longer reports the default namespace http://tempuri.org/, and its WSDL reveals that its default namespace is now http://YesU.Can.AndOverride.it/ as expected.

Answer 2

The custom attribute you are applying would need to be configured like this[AttributeUsage(System.AttributeTargets.Class, Inherited = true)]

see previous thread

How does inheritance work for attribtues?