How to Debug a Visual Studio Extension

Here are a few tips for debugging Visual Studio Extensions.

Visual Studio 2008/2010

If you need to debug your Visual Studio extension, you may find that Visual Studio itself locks it. This is a real drag – to resolve this issue, add the following as a pre-build step:

if exist "$(TargetPath).locked" del "$(TargetPath).locked"
if not exist "$(TargetPath).locked" if exist "$(TargetPath)" 
move "$(TargetPath)" "$(TargetPath).locked"

This will ensure the locked file is moved out of the way first – very useful!

Visual Studio 2010

Every time I do a clean checkout of one of my projects, it seems to lose the ability to be run in the Experimental mode of visual studio. Here’s a quick tip – if you lose the ability to debug your visual studio extension, make sure you have the ‘Debug’ tab of your project set up as below:

Specifically with the external program set as visual studio and the command line arguments as /rootsuffix exp. This will run your extension in the Experimental Instance of Visual Studio.


Getting Source Code Metrics from SVN

Lets say that we need to find out how many lines of code exist in a branch, or how many lines are checked in by a specific user. Let’s ignore the usefulness of these metrics, just assume that they’re needed (realistically, lines of code isn’t a very useful metric, but perhaps you want to have a quick idea of how much has gone into a release). How do we do this?

TortoiseSVN statistics aren’t really enough. Here’s some alternatives:

I’d recommend taking a look at FishEye if you’re going to go to the effort of getting these statistics. Any comments on alternatives would be welcome!


IDataServiceMetadataProvider Entities Missing in $metadata

If you are following through the example on creating custom data service providers as on this blog:


And you notice that your entities are not showing up in the $metadata file, double check that you have added this:

public class service : MyNewDataService
        // This method is called only once to initialize service-wide policies.
        public static void InitializeService(DataServiceConfiguration config)
            config.SetEntitySetAccessRule("*", EntitySetRights.AllRead);
            config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2;
Just remember to set the entity set access rules for all entities - other they won't show up!

Composite Data Service Framework

Today I start a new project – the Composite Data Service Framework. The Composite Data Service Framework is a project that aims to obviate some of the limitations of WCF Data Services, specifically:

  • Allowing multiple data services to be aggregated in a single data service.
  • Providing more support for Service Operations (such as auto-generation of proxies client-side).
  • Aggregating different service types (entity framework, CLR types etc)
  • Complementing OData services with traditional WCF services with a single definition of proxies client-side.

The project is in its early stages and is hosted at:


More updates will follow.


Data Service Exception “Unauthorised” when connecting to Sharepoint OData

If you are struggling to fetch data from a Sharepoint OData service and getting an error as below:

 [DataServiceClientException: Unauthorized]
   System.Data.Services.Client.QueryResult.Execute() +436914
   System.Data.Services.Client.DataServiceRequest.Execute(DataServiceContext context, QueryComponents queryComponents) +133 

Then ensure you are setting the Credentials property of your Data Service Context, as below:

//  Create the data context.
SharepointDataContext dc = new SharepointDataContext(new Uri("http://dksp/_vti_bin/listdata.svc"));
//  Provide default credentials, without this authorisation will fail!
dc.Credentials = System.Net.CredentialCache.DefaultCredentials;

//  Etc...
var accounts = from a in dc.Accounts select a;

Just another issue you may come across when using Sharepoint OData services!


The “Name attribute is invalid” when adding a Service Reference to a Sharepoint OData Service

Well this little issue took me a while to investigate, but the skinny is this:

If you are going to add a service reference to a Sharepoint OData service (e.g. http://sharepoint/_vti_bin/listdata.svc) then make sure your Sharepoint site name does NOT begin with a number – otherwise Visual Studio will fail to add the reference.

Quick and easy, but this took quite a while for me to find, hope it helps anyone in the same situation!


Apex 1.2 Released

Apex 1.2 has been released, with some new features:

  • The ‘Compatibility’ namespace, which contains classes to address compatibility issues between WPF, Silverlight and WP7.
  • The ‘Asynchronous Command’ object, which provides a powerful way to use Asynchronous Commands in MVVM.
The release is at: http://apex.codeplex.com/