How Can I Identify the Object Type Passed to a C Function?

Identifying Object Type in C

In C , determining the type of an object passed as a parameter can be essential for handling polymorphic classes and their derived classes. This scenario arises when a function overrides another function that accepts an object of a base class, but the overriding function requires access to specific functions available only in derived classes.

To resolve this issue, dynamic_cast can be employed to cast the object from the base class type to the derived class type, allowing you to check if the object belongs to the desired derived class.

TYPE& dynamic_cast<TYPE&> (object);
TYPE* dynamic_cast<TYPE*> (object);

Dynamic_cast performs a runtime check to verify the validity of the cast. If the cast is to a pointer or reference of a type that does not match the actual object type, the result will be NULL or throw a bad_cast exception, respectively.

It's important to note that dynamic_cast requires the base class to have at least one virtual function to function correctly. This is because runtime type information (RTTI) is only available for polymorphic classes. In practice, most base classes already have a virtual destructor to allow derived class objects to clean up properly when deleted from a base pointer.

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