public void AddRange(ICollection assemblies)
            {
                this.BeginUpdate();
                try
                {
                    foreach (IAssembly assembly in assemblies)
                    {
                        AssemblyNode assemblyNode = new AssemblyNode(assembly);
                        if (assemblyNode.IsValid())
                        {
                            this.Nodes.Add(assemblyNode);

                            if (this.SelectedNode == null)
                            {
                                this.SelectedNode = assemblyNode;
                            }
                        }
                    }
                }
                finally
                {
                    this.EndUpdate();
                }
            }