ConfigurationManager::Count Property

public void CodeExample(DTE2 dte, AddIn addin)
{   // Make sure you have a solution loaded into Visual Studio
    // before running the following example.
    try
    {
        ConfigurationManager configmgr;
        Configuration config;
        if (dte.Solution.Projects.Count > 0)
        {
            configmgr = dte.Solution.Projects.Item(1).ConfigurationManager;
            // Return the ActiveConfiguration.
            config = configmgr.ActiveConfiguration;
            // Show how many Configuration objects are in the 
            // Configuration Manager.
            MessageBox.Show(configmgr.Count.ToString());
            // Show the name of the application containing this 
            // Configuration Manager.
            MessageBox.Show(configmgr.DTE.Name);
            // Show the parent object
            MessageBox.Show(((Project)configmgr.Parent).Name);
        }
    }
    catch(Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
}