Why does “WCF Test Client” preempt my WCF app, and

My simple sample wcf service WAS working, but then all of a sudden it started prompting me for an endpoint address in a "WCF Test Client" dialog.

I can't recall changing anything that would cause it to go from popping up the browser (IE 8) when I hit F5 to now displaying this "WCF Test client" thing.

I didn't know what to enter into the edit box it provided, so I tried "http://localhost:4841/RestServiceImpl.svc" (http://localhost:4841/RestServiceImpl.svc/xml/123 still works from outside of Visual Studio)

It accepted that ("Service added successfully" displays in the dialog's task bar), but does nothing else; and clicking the "My Service Projects" Treeview does nothing (it has no children).

UPDATE

If I attempt to run the new operation directly from IE8, I get:

Server Error in '/' Application.

In contract 'IRestServiceImpl', there are multiple operations with Method 'GET' and a UriTemplate that is equivalent to 'xml/{platypusId}'. Each operation requires a unique combination of UriTemplate and Method to unambiguously dispatch messages. Use WebGetAttribute or WebInvokeAttribute to alter the UriTemplate and Method values of an operation.

Does this mean I can only have one xml-returning operation that takes a string? The other/original method is ...xml/{id}...

UPDATE 2

This is the code, and it's still failing:

[ServiceContract]
public interface IRestServiceImpl
{
    [OperationContract(Name="Foo")]
    [WebInvoke(Method = "GET",
        ResponseFormat = WebMessageFormat.Xml,
        BodyStyle = WebMessageBodyStyle.Wrapped,
        UriTemplate = "xml/{id}")]
    string XMLData(string id);

    [OperationContract(Name="FooBar")]
    [WebInvoke(Method = "GET",
        ResponseFormat = WebMessageFormat.Xml,
        BodyStyle = WebMessageBodyStyle.Wrapped,
        UriTemplate = "xml/{platypusId, anotherId}")]
    string FirstTrial(string platypusId, string anotherId);

    [OperationContract(Name="FooFooBar")]
    [WebInvoke(Method = "GET",
        ResponseFormat = WebMessageFormat.Json,
        BodyStyle = WebMessageBodyStyle.Wrapped,
        UriTemplate = "json/{id}")]
    string JSONData(string id);
}

// Implementation (.svc) file

public class RestServiceImpl : IRestServiceImpl
{
    public string XMLData(string id)
    {
        return "You requested product " + id;
    }

    public string FirstTrial(string platypusId, string anotherID)
    {
        return "I reckon so" + platypusId + anotherID;
    }

    public string JSONData(string id)
    {
        return "You requested product " + id;
    }
}

回答1:

For any type of web service, you cannot have overloaded methods. WCF allows this if you specify a different OperationContract Name E.G.

[ServiceContract]
interface IService
{
    [OperationContract(Name="Foo")]
    void Foo();

    [OperationContract(Name="Foobar")]
    void Foo(string bar);

}

But this is basically changing the public signature to the method, even though it is named the same in the interface, so I would generally just not do this, since it can be more confusing when creating your clients.

Updated:

Make sure that you have autoformateselectionenabled to true in your web.config.

<endpointBehaviors>
    <behavior name="web">
        <webHttp automaticFormatSelectionEnabled="true"/>
    </behavior>
</endpointBehaviors>

" This will automatically set the response format as per request type (JSON/XML)"

回答2:

You can have more than one method that takes a String and returns XML, but you can't name them the same thing and have them both be GET methods. How would it know which one you are intending to call?