- When converting the code to IL, we observe that abstract methods are called using the callvirt instruction. This signifies that they are virtual by nature and rely on a runtime mechanism called the vtable (virtual table).
IL Abstract.
A vtable is a per-class table that holds references to the implementations of virtual and abstract methods. This table allows derived classes to override the base class's abstract or virtual methods. At compile time, the compiler ensures that the derived class refers to the base class’s vtable and updates the entries to point to the correct implementations from the derived class.
IL override
This mechanism inherently relies on object instances to resolve the method calls at runtime, which is why abstract methods are tied to instance-based polymorphism.
- However, static methods work entirely differently in C#. They are not associated with instances of a class but rather with the class itself. Static methods are resolved at compile time based on the type, and they do not participate in the vtable mechanism. Because static methods are not tied to an instance, there is no runtime resolution, and they cannot be overridden or abstracted like instance methods.IL Static
Due to this fundamental difference, it is not possible to define static abstract methods in a class. The runtime has no mechanism to support such behavior, as it would require combining type-level resolution (for static methods) with instance-level polymorphism (for abstract methods), which is not supported in C#.
The implementation has already been written above
