Why is the ListBox displaying the type name of the objects in the list instead of the value of a property in the object

By default when you bind the ListBox’s ItemsSource to a collection of objects of a custom type, the ListBox would simply call the object’s ToString() method to determine what to display for each item. The ToString method would normally simply display the type name of the object.

If you instead want a value of a property of the object to be displayed in the listbox, you should set the DisplayMemberPath property of the ListBox to that property name as follows:

<ListBox ItemsSource='{StaticResource myCollection}' DisplayMemberPath='FirstName' />