Editing Method (computer programming) (section)

====Example====
In C#, a virtual method can be overridden with an abstract method. (This also applies to Java, where all non-private methods are virtual.)
<syntaxhighlight lang="csharp">
class IA
{
    public virtual void M() { }
}
abstract class IB : IA
{
    public override abstract void M(); // allowed
}
</syntaxhighlight>

Interfaces' default methods can also be reabstracted, requiring subclasses to implement them. (This also applies to Java.)
<syntaxhighlight lang="csharp">
interface IA
{
    void M() { }
}
interface IB : IA
{
    abstract void IA.M();
}
class C : IB { } // error: class 'C' does not implement 'IA.M'.
</syntaxhighlight>