protected C# with Example

The protected keyword marks field, methods properties and nested classes for use inside the same class and 
derived classes only: 
public class Foo() 
{ 
protected void SomeFooMethod() 
{ 
//do  something 
} 
protected class Thing 
{ 
private string blah; 
public int N { get; set; } 
} 
} 
public class Bar() : Foo 
{ 
private void someBarMethod() 
{ 
SomeFooMethod(); // inside derived class 
var thing = new Thing(); // can use nested class 
} 
} 
public class Baz() 
{ 
private void someBazMethod() 
{ 
var foo = new Foo(); 
foo.SomeFooMethod(); //not  accessible  due  to  protected  modifier 
} 
}