How to unit test server controls on postback?

Question

I am trying to create my own EasyBinderDropDown that currently looks like this:

public class EasyBinderDropDown : DropDownList, ICanBindToObjectsKeyValuePair {
        public void BindToProperties<TYPE_TO_BIND_TO>(IEnumerable<TYPE_TO_BIND_TO>
                  bindableEnumerable,
        Expression<Func<TYPE_TO_BIND_TO, object>> textProperty, 
        Expression<Func<TYPE_TO_BIND_TO, object>> valueProperty) {...}
        public bool ShowSelectionPrompt { get; set; }
        public string SelectionPromptText { get; set; }
        public string SelectionPromptValue { get; set; }
    //...
}

Basically it is very helpful for easy binding to objects from inside code since you just do something like _dropDown.BindToProperties(myCustomers, c=>c.Name, c=>c.Id) and it works for you, also by setting ShowSelectionPrompt and SelectionPromptText I can easily have a "Select Customer" Line. I don't want to ask so much about my specific implementation, rather I am confused how to write unit tests for some scenarios.

For example my current tests cover the control being created properly during load and having its output render properly but I am lost as to how to test what happens when the control gets posted back. Can anyone give me some advice on how to test that? I would prefer to do this without having to mock an HTTPContext or anything like that, Is there a way I can simulate the control being rebuilt?

Answer 1

"I would prefer to do this without having to mock an HTTPContext or anything like that, Is there a way I can simulate the control being rebuilt."

By definition, you are not asking to "unit test"; you are looking for an "integration test". If you are not mocking the major dependencies, in this case, the ASP.NET runtime components, the what you are testing is the integration between your control and ASP.NET.

If you do not want to mock out the HttpContext and friends, then I would suggest an automated web testing framework such as Selenium or NUnitAsp.