Editing Method overriding (section)

===C#===
[[C Sharp (programming language)|C#]] does support method overriding, but only if explicitly requested using the modifiers {{C sharp|override}} and {{C sharp|virtual}} or {{C sharp|abstract}}.

[[File:Csharp method overriding.svg]]

<syntaxhighlight lang="csharp">
abstract class Animal
{
    public          string Name { get; set; }
    // Methods
    public          void   Drink();
    public virtual  void   Eat();
    public          void   Go();
}

class Cat : Animal
{
    public new      string Name { get; set; }
    // Methods
    public          void   Drink();  // Warning: hides inherited drink(). Use new
    public override void   Eat();    // Overrides inherited eat().
    public new      void   Go();     // Hides inherited go().
}
</syntaxhighlight>

When overriding one method with another, the [[Type signature|signatures]] of the two methods must be identical (and with same visibility). In C#, [[class method]]s, [[Indexer (programming)|indexer]]s, [[Property (programming)|properties]] and events can all be overridden.

Non-virtual or static methods cannot be overridden. The overridden base method must be ''virtual'', ''abstract'', or ''override''.

In addition to the modifiers that are used for method overriding, C# allows the '''hiding''' of an inherited property or method. This is done using the same signature of a property or method but adding the modifier {{C sharp|new}} in front of it.<ref>{{cite web
| accessdate = 2011-08-02
| date       = 2002-03-25
| first      = Hanspeter
| last       = Mössenböck
| pages       = 6–8
| publisher  = Institut für Systemsoftware, Johannes Kepler Universität Linz, Fachbereich Informatik
| title      = Advanced C#: Overriding of Methods
| quote      = 
| url        = http://ssw.jku.at/Teaching/Lectures/CSharp/Tutorial/Part2.pdf}}
</ref>

In the above example, hiding causes the following:

<syntaxhighlight lang="csharp">
Cat cat = new Cat();

cat.Name = …;             // accesses Cat.Name
cat.Eat();                // calls Cat.Eat()
cat.Go();                 // calls Cat.Go()
((Animal)cat).Name = …;   // accesses Animal.Name!
((Animal)cat).Eat();      // calls Cat.Eat()!
((Animal)cat).Go();       // calls Animal.Go()!
</syntaxhighlight>