问题
I am trying to create UML diagrams but can not mark a class as Abstract. Please help.
回答1:
Right-click on the class, either in a static structure diagram, or in the Model Explorer. Activate the "Properties" context menu item to bring up the properties dialog for that class.
On the first tab, check the "IsAbstract" checkbox.
The class will now be displayed in italics.
来源：https://stackoverflow.com/questions/1712340/visio-2003-uml-class-diagrams-abstract-class