virtual1.cpp

#include <iostream> 
#include <string>

class Sample1 {
public:
    virtual void vMethod1() {
        printf("This is virtual method 1\n");
        printf("member1 = %d\n", member1);
    }
    virtual void vMethod2() {
        printf("This is virtual method 2\n");    
    }
    void method2() {
        printf("This is NONVIRTUAL method 2\n");    
    }
public:
    int     member1;
    int     member2;
};

//Define method type
//Thêm tham số thisPtr ở đây
typedef void (*MyFunc)(Sample1 *thisPtr);

int main(int argc, const char * argv[]) {
    Sample1 *a = new Sample1();
    
    a->member1 = 1000;
    printf("size of Sample1: %d\n", sizeof(Sample1));
    
    MyFunc *virtualMethodTable = (MyFunc*)(*(MyFunc*)a);    
    //Lệnh trên tương đương với:
    //    memcpy(&virtualMethodTable2, b, 8);

    virtualMethodTable[0](a); //call method1
    virtualMethodTable[1](a); //call method2
    
    return 0;
}