r6025 pure virtual function call

Definition of virtual function:A member function declared in a base class as virtual and redefined in one or more derived classes: The virtual function returns the type function name (parameter table) {

Let's look at the invocation of the virtual member function. The class C041 contains virtual member functions, which are defined as follows: struct C041{C041() : c_(0x01) {}virtual void foo() { c_ = 0x02; }char c_;}; Execute the following code: C041 obj;PRINT_DETAIL(C041, obj)PRINT_VTABLE_ITEM(obj, 0, 0)obj.foo()

The following program is adapted from instrument4.cpp of thinking in C ++. # Include The disassembly process for calling the virtual function w-> wind () is as follows: W-> what (); Explanation: BeginW = 0x97b1008 W = 0xbfab8bbc* W = 0x80489f0 Mov-0xc (% EBP), % eax% Eax = W = 0x97b1008Is a pointer. Like this, it points to the first address of the wind object, and also to the vptr of the wind object. MoV

Item 09-Never invoke virtual functions in constructors and destructors (never call virtual functions during construction or destruction)Why?Since the base class constructor executes earlier than the derived class constructor, the member variables of the base class constructor executing derived class have not been initialized. If the

It means that the initialize () member function of Class A cannot be called without an object (); Context: Void B: Initialize (INT argc, char ** argv) { ··· A: Initialize (argc, argv ); ··· } Modification method: 1. Class B inherits Class Class B: public { } 2. Create a new a object, A aa; AA. initialize (argc, argv ); 3,Define function getanimationname () as static