系列1：C#訪問限制符

 

C# Access Modifier	Meaning in Life
public	Marks a member as accessible from an object variable as well as any derived classes.
private	Marks a method as accessible only by the class that has defined the method. In C#, all members are private by default.
protected	Marks a method as usable by the defining class, as well as any derived classes. Protected methods, however, are not accessible from an object variable.
internal	Defines a method that is accessible by any type in the same assembly, but not outside the assembly.
protected internal	Defines a method whose access is limited to the current assembly or types derived from the defining class in the current assembly.

Code
    class Program
    {
        static void Main(string[] args)
        {
            // Make an object and attempt to call members.
            SomeClass c = new SomeClass();
            c.PublicMethod();
            c.InternalMethod();
            c.ProtectedInternalMethod();
            c.PrivateMethod(); // Error!
            c.ProtectedMethod(); // Error!
            c.SomeMethod(); // Error!
        }
        // Member visibility options.
        class SomeClass
        {
            // Accessible anywhere.
            public void PublicMethod() { }
            // Accessible only from SomeClass types.
            private void PrivateMethod() { }
            // Accessible from SomeClass and any descendent.
            protected void ProtectedMethod() { }
            // Accessible from within the same assembly.
            internal void InternalMethod() { }
            // Assembly-protected access.
            protected internal void ProtectedInternalMethod() { }
            // Unmarked members are private by default in C#.
            void SomeMethod() { }
        }
    }