What are the valid access specifier used for the declaration of class at namespace level?
In C#, the valid access specifiers that can be used for the declaration of a class at the namespace level are:
-
public: When a class is declared as 'public', it can be accessed from any other code in the same assembly or from other assemblies that reference it. This is the most permissive access level.
-
internal: The 'internal' access specifier allows a class to be accessed only within the same assembly. It restricts the access to code outside the assembly, even if it is part of the same namespace.
-
protected internal: This access specifier allows a class to be accessed within the same assembly, as well as from derived classes in other assemblies. It combines the behavior of both the protected and internal access specifiers.
It's important to note that the private access specifier is not valid for a class at the namespace level. The private access specifier is used to restrict access to members within the scope of the defining class, and it cannot be applied to a class itself at the namespace level.
Here's an example demonstrating the usage of access specifiers for class declarations at the namespace level:
namespace MyNamespace
{
public class PublicClass
{
// This class can be accessed from anywhere.
}
internal class InternalClass
{
// This class can only be accessed within the same assembly.
}
protected internal class ProtectedInternalClass
{
// This class can be accessed within the same assembly and from derived classes in other assemblies.
}
// Private access specifier is not valid for a class at the namespace level.
// private class PrivateClass { }
}
In the above example, we have a namespace 'MyNamespace' that contains classes with different access specifiers. 'PublicClass' is declared as 'public', 'InternalClass' is declared as 'internal', and 'ProtectedInternalClass' is declared as protected internal. The commented 'PrivateClass' declaration is invalid because private is not a valid access specifier for a class at the namespace level.