问题
On a public class in C# is there a way to make a field/method accessible only to derived classes within the same assembly?
From what I understand protected internal in C# means the same as protected or internal (ie accessible to derived classes or classes from the same assembly), which is not what I need.
回答1:
What if you removed the "internal" only fields/methods from the public class to an internal class. Then all of the classes in that assembly could derive from the internal class:
public abstract class MyClass
{
public string Name { get; set; }
}
// Only classes in this assembly can derive from this class
internal abstract class InternalClass : MyClass
{
protected string Other { get; set; }
}
回答2:
You can't prevent a class from an external assembly from compiling a call to it, but you can force an exception to occur at runtime if they do by putting this attribute on your protected member:
[System.Security.Permissions.StrongNameIdentityPermission(
System.Security.Permissions.SecurityAction.LinkDemand,
PublicKey = "...<Your assembly's full public key>...")]
回答3:
If the class is internal, there will be no way to sub-class it outside of the assembly. Make the fields/methods protected and you're good to go.
If the class must be public, use an internal sub-class everywhere within your assembly.
来源：https://stackoverflow.com/questions/4271548/make-field-method-accessible-only-to-derived-classes-within-same-assembly