Internal & Protected Internal

Question

Can any one explain to me c# access specifiers Internal & Protected Internal with example?

Vulpes · Answer

Here's a simple example to illustrate the difference between the two. First compile the following as a dll called testdll.dll: // testdll.cs public class MyClass { internal int MyInt = 3; protected internal int MyOtherInt = 4; } public class YourClass { public int GetMyInt() { MyClass mc = new MyClass(); return mc.MyInt; // OK as MyInt is internal } public int GetMyOtherInt() { MyClass mc = new MyClass(); return mc.MyOtherInt; // OK as MyOtherInt is internal as well as protected } } Now compile the following as an exe called testexe.exe after first adding a reference to testdll.dll: // testexe.cs using System; class Test { static void Main() { OurClass oc = new OurClass(); Console.WriteLine(oc.GetMyOtherInt()); // 4 Console.ReadKey(); } } class OurClass : MyClass // inherits from MyClass { /* GetMyInt doesn't compile because MyInt is internal and so only accessible in its own assembly public int GetMyInt() { return MyInt; // Not OK as MyInt is internal } */ public int GetMyOtherInt() { return MyOtherInt; // OK as MyOtherInt is protected as well as internal } } Notice that 'protected internal' in C# means 'protected OR internal'. The CLR also has the concept of 'protected AND internal' which means that the member is only accessible from within its class or within a derived class in the same assembly. It's never accessible from a different assembly. However neither C# nor VB.Net supports protected AND internal (however C++/CLI and CIL do) so this is academic unless you're using reflection to create a class dynamically.

Gomathi Palaniswamy · Answer

Internal - The internal can be accessed from same name assembly but not by some other assembly like public. Protected internal - The protected internal can be accessed by same assembly and derived assembly.

Mayur Gujrathi · Answer

refer this