c# - 以下代码中 protected 内部访问说明符的意义

Question

好的，让我从一个例子开始。这是我在另一个程序集中的基类

namespace BL
{
    public class BasicClass
    {
        protected internal void func()
        {
            //Code Logic
        }
    }
}

现在这是我在另一个程序集中的派生类

namespace DL
{
    public class DerivedClass:BasicClass
    {
        private void hello()
        {
            func();
        }
    }
}

我可以从基类调用 func() ，因此它表明 protected 访问修饰符属性但是 internal 访问修饰符属性。是否应该允许它在另一个程序集中访问 func()，因为它声明为 internal。如果是这样，那么为什么称它为 protected internal 而不是简单的 protected

Answer 1

你可能想给 this阅读。

The protected internal accessibility level means protected OR internal, not protected AND internal. In other words, a protected internal member can be accessed from any class in the same assembly, including derived classes. To limit accessibility to only derived classes in the same assembly, declare the class itself internal, and declare its members as protected.