在两个项目中都定义了 Electro_Spec.Masters.MasterPage 类.

The Electro_Spec.Masters.MasterPage class is defined in both projects.

从两个项目之一中删除 Electro_Spec.Masters.MasterPage ，或更改两个 MasterPage 类之一的名称空间.

Remove the Electro_Spec.Masters.MasterPage from one of the two projects or change the namespace for one of the two MasterPage classes.