C# Language Specification

Class modifiers

A class-declaration may optionally include a sequence of class modifiers:

class-modifiers:
class-modifier
class-modifiers class-modifier

class-modifier:
new
public
protected
internal
private
abstract
sealed
static

It is a compile-time error for the same modifier to appear multiple times in a class declaration.

The new modifier is permitted on nested classes. It specifies that the class hides an inherited member by the same name, as described in §10.3.4. It is a compile-time error for the new modifier to appear on a class declaration that is not a nested class declaration.

The public, protected, internal, and private modifiers control the accessibility of the class. Depending on the context in which the class declaration occurs, some of these modifiers may not be permitted (§3.5.1).

The abstract, sealed and static modifiers are discussed in the following sections.

1.