用户控件和自定义控件库的区别

I'm working on creating a date/time user control in WPF using C# 2008. My first user control. I'm also using Matthew MacDonald's book, "Pro WPF in C# 2008". In that book he strongly recommended creating a user control using the WPF Custom Control Library project template; so I followed his suggestion. I've finished writing the code which would go into what I think of as the code-behind file. Now I'm ready to write the XAML.I'm working on creating a date/time user contro