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Using the sizeof operator, I can determine the size of any type – but how can I dynamically determine the size of a polymorphic class at runtime?
For example, I have a pointer to an Animal, and I want to get the size of the actual object it points to, which will be different if it is a Cat or a Dog. Is there a simple way to do this, short of creating a virtual method Animal::size and overloading it to return the sizeof of each specific type?
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We also know that the class size is defined as the difference between the actual upper limit and actual lower of a given class interval. Therefore, the class size for the class interval 10-20 is 10.
The size of object of a class depends on the no. of bytes occupied by the data members of the class. }; The object of class student will occupy space of 8 bytes.
In C++, the Size of an empty structure/class is one byte as to call a function at least empty structure/class should have some size (minimum 1 byte is required ) i.e. one byte to make them distinguishable.
If you know the set of possible types, you can use RTTI to find out the dynamic type by doing dynamic_cast. If you don't, the only way is through a virtual function.
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