Getting Started with Prism 2.1 for WPF

using System;
using System.Windows.Input;

namespace Prism2Demo.Modules.Navigator
{
    public class ShowWorkspaceBCommand : ICommand
    {
        #region Fields

        // Member variables
        private readonly NavigatorViewModel m_ViewModel;
        private readonly string m_WorkspaceBName = "WorkspaceB";

        #endregion

        #region Constructor

        public ShowWorkspaceBCommand(NavigatorViewModel viewModel)
        {
            m_ViewModel = viewModel;
        }

        #endregion

        #region ICommand Members

        public bool CanExecute(object parameter)
        {
            return m_ViewModel.ActiveWorkspace != m_WorkspaceBName;
        }

        public event EventHandler CanExecuteChanged
        {
            add { CommandManager.RequerySuggested += value; }
            remove { CommandManager.RequerySuggested -= value; }
        }

        /// <summary>
        /// ShowWorkspaceB
        /// </summary>
        public void Execute(object parameter)
        {
            CommandServices.ShowWorkspace(m_WorkspaceBName, m_ViewModel);
        }

        #endregion
    }
}