Skip to content
Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

abstract class

A class you can't create directly; it exists to be derived from.

An abstract class cannot be instantiated and may declare abstract members that non-abstract derived classes must override.

Examples

  • abstract class Shape { public abstract double Area(); } compiles, but new Shape() is error CS0144.

See also

interface virtual method sealed
Read the full section →