Class Virtual Functions
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Class virtual methods are virtual methods tagged with the __classmethod modifier. They are invoked via the VMT, but the this pointer is the metaclass pointer, not an object instance as for non-class virtuals.
Use the __classmethod keyword to declare class methods in C++. The modifier __classmethod indicates that a function may be invoked on a class name -- as well as on an instance of that class.
Note: C++Builder also supports virtual __classmethod members, and you can invoke these methods from C++.
For a code snippet that shows how to use the __classmethod keyword, see Class Methods Using __classmethod Keyword.