摘要：
父类 = 子类 协变 in don't safty子类 = 父类 逆变 out委托public delegate T MyFuncB<out T>(); 协变public delegate void MYActionB<in T>(T param); 逆变public delegate T MyFuncB<out T>(); //支持协变MyFuncB<object> funcBObject = null;MyFuncB<string> funcBString = null;funcBObject = funcBString; 阅读全文
