Several system types extend MarshalByRefObject but also perform security checks at runtime to prevent anything outside the application domain from invoking an object of that type remotely.

• 有些系统类型扩展了MarshalByRefObject,但它们在运行时仍会执行安全检查,目的是防止应用程序域之外的任何代码远程调用属于该类型的对象。