Manage namespaces in VB.NET class library projects

HOW-TO
Manage namespaces in VB.NET class library projects, to allow using the classes defined in one project in another project be referencing them with the names they were define with.

PROBLEM
Let’s take a look at the following example:

We start with two projects: a class library project and an application project that references to the first one. In all the vb files in the class library project we use the ClassLibrary namespace. One might expect to access the classes from the class library project in the application project by including the ClassLibrary namespace. However, this will result in an invalid reference error.

The reason for this is that VB adds the value of the ProjectName property to the beginning of the namespaces defined in a project. In this way, if the ProjectName is set to CustomControls, and the namespace is ClassLibrary, the full namespace name will become CustomControls.ClassLibrary.

SOLUTION
To avoid this, in the VB class library project properties, you should leave the RootNamespace text field empty. This will allow you to access the classes only by using the ClassLibrary namespace.