Pointer-based operations are less frequently needed than they might seem. For instance, examine this class declaration:
class PointerMisuse{private: CDC * m_pDeviceContext;public: PointerMisuse(); ~PointerMisuse();};PointerMisuse::PointerMisuse(){ m_pDeviceContext = new CDC;}PointerMisuse::~PointerMisuse(){ delete m_pDeviceContext;}
Even experienced programmers are often inclined to this programming style of declaring pointers and allocating objects on the free store. This is not surprising — after all, classes like this one are widely used in many commercial frameworks (MFC, ATL, and many others). But it isn’t really necessary to use pointers and dynamic memory allocation here. You can rewrite the class like this:
class ProperUse{private: CDC * m_pDeviceContext; CDC cdc; //automatic storagepublic: ProperUse();};ProperUse::ProperUse(){ m_pDeviceContext = &cdc;}
Not only is this version safer (remember that dynamic memory allocations might fail); it is also simpler and more efficient because it avoids the unnecessary overhead of memory allocation and deallocation at runtime. Note that the use of pointers now becomes redundant, and the member m_pDeviceContext is not needed anymore. However, to ensure backward compatibility with existing code, it is still used.