#345 – WPF Command Model is Preferred over Traditional Event Handler Model

In an application, you often need to execute some code in response to a user action.  In WPF, you can use the new command model to respond to user actions or you can use the event handler model that Windows Forms used.

In the event handler model, you wire up event handlers to the code that does the actual work.

With this approach, you still have to add all of the individual event handlers and you need to write code to manage state, i.e. figure out when the user is allowed to click the buttons/menus and enable/disable them.

In the WPF command model, a single command object is bound to the handler code and each control links to that command.  The command object also adds support for state.

So the benefits of the WPF command model are:

• Less plumbing code to write (no event handlers)
• Automatically handle control enabled/disabled state