Testing Linqto SQL classes

Question

How do I unit test my code that has LTS Datacontext. I get error while testing, I have a lot of Datacontexts and manually adding the Connection string is a pain, any suggestions.

Answer 1

Well, the way I do it is as follows:

My Data Layer has an interface, such as follows:

public class MyDataLayer : iMyDataLayer
{
  public string GetMyData(parameters)
  {
    return myQueryValue;
  }

}

public interface iMyDataLayer
{
  public string GetMyData(parameters);
}

Now, in my constructor for my main code base (business logic) I will have a parameter to pass in the interface for the data layer:

private iMyDataLayer DataLayer;

public class MyBusinessLogic(iMyDataLayer dataLayer)
{
   DataLayer = dayaLayer
}

public string GetMyData(parameters)
{
  return DataLayer.GetMyData(parameters)
}

With this, i can now create a "fake" data service in my TDD project:

public class FakeDataLayer : iMyDataLayer
{
      public string GetMyData(parameters)
      {
        return "Some Default Value or Object";
      }

}

So now when i run my test, I can now pass in my fake data layer object to my business logic, from here it will invoke the fake logic and get back a default result.

Now, granted you won't be working with real data here. However, if you setup fake objects with real valid/invalid data, you can test your business logic this way without having to connect to a database.

Hope this helps. Let me know if you need clarification on anything.