结构体类型强转类类型

#include "stdafx.h"
#include <memory.h>

typedef struct tagTest
{
    int a;
    int b;
    int c;
}TEST;

class CParentTest
{
public:
    int GetC(void){return c;};
protected:
private:
    int c;
};

class CTest : public CParentTest
{
public:
    int GetA(void){return a;};
    int GetB(void){return b;};    
protected:
private:
    int a;
    int b;    
};

int main(int argc, char* argv[])
{
    TEST oTest;
    memset(&oTest, 0, sizeof(TEST));
    oTest.a = 10;
    oTest.b = 20;
    oTest.c = 30;

    CTest* pCTest = (CTest*)&oTest;
    int a = pCTest->GetA(); // 20

    int b = pCTest->GetB();    // 30

    int c = pCTest->GetC();    // 10


    return 0;
}