Custom error handling in webmethod returning XmlDocument

Question

I'm working with a client who has a web method like this:

[WebMethod]
public XmlDocument Send(string stuff)
{
    // ...
}

At present, there's a class of exceptions which occur which the code is re-throwing, triggering ASP.Net's standard handling of exceptions.

We'd like to change it so that the webmethod still returns status code 500, but with some text/plain diagnostic information we provide rather than the default ASP.Net stuff.

What's the appropriate way to do that?

I've made it work, using Context.Response.End like this:

[WebMethod]
public XmlDocument Send(string stuff)
{
    try
    {
        // ...normal processing...

        return xmlDocument;
    }
    catch (RelevantException)
    {
        // ...irrelevant cleanup...

        // Send error
        Context.Response.StatusCode = 500;
        Context.Response.Headers.Add("Content-Type", "text/plain");
        Context.Response.Write("...diagnostic information here...");
        Context.Response.End();
        return null;
    }
}

But that feels hacky, so I'm hoping there's a better answer.

Answer 1

But that feels hacky, so I'm hoping there's a better answer.

It feels hacky because it is hacky.

The better answer is: Return XML, like you said you would, with whatever information it is you want to include. The service returns XML, it was intended for code, not people, to consume.

[WebMethod]
public XmlDocument Send(string stuff)
{
    try
    {
        // ...normal processing, creates xmlDocument...

        return xmlDocument;
    }
    catch (RelevantException)
    {
        // ...irrelevant cleanup...

        // ...error processing, creates xmlDocument...
        Context.Response.StatusCode = 500;
        return xmlDocument;
    }
}