Visual C# Reference: Errors and Warnings
Compiler Error CS0012
Error Message
The type 'type' is defined in an assembly that is not referenced. You must add a reference to assembly 'assembly'.The definition for a referenced type was not found. This could occur if a required .DLL file is not included in the compilation. For more information, see Add Reference Dialog Box and /reference (Import Metadata) (C# Compiler Options).
The following sequence of compilations will result in CS0012:
// cs0012a.cs // compile with: /target:library public class A {}
Then:
// cs0012b.cs // compile with: /target:library /reference:cs0012a.dll public class B { public static A f() { return new A(); } }
Then:
// cs0012c.cs // compile with: /reference:cs0012b.dll class C { public static void Main() { object o = B.f(); // CS0012 } }
You could resolve this CS0012 by compiling with /reference:cs0012b.dll;cs0012a.dll, or in Visual Studio by using the Add Reference Dialog Box to add a reference to cs0012a.dll in addition to cs0012b.dll.
我碰到这个错误是因为用到了一个类中的静态方法,而该类又实现了一个借口,而我又没有引用该接口。
解决办法很简单,在vs里面添加对接口的引用就可以了。就像上面所说的,根本问题在于类的连环引用。