#include <iostream>

 #include <string>

 #include <stdio.h>

 #include <stdlib.h>

 using namespace std;

 struct Person

 {

     int age;

     int id;

 };

 template <class T> T myRead(void * memory)

 {

     char buffer[sizeof(T)];

     memcpy(buffer, memory, sizeof(T));

     T temp = *((T *)buffer);  // 调用 Person 拷贝构造

     return temp;

 }

 template <class T> T myRead2(void * memory)

 {

     T temp;

     memcpy(&temp, memory, sizeof(T));

     return temp;

 }

 template <class T> T* myRead3(void * memory, int offset)

 {

     T* temp = new T;

     memcpy(temp, (char*)memory+offset, sizeof(T));

     return temp; //返回指针, 有内存泄漏风险

 }

 template <class T> void myRead4(void * memory, int offset, T* data)

 {

     memcpy(data, (char*)memory+offset, sizeof(T));

 }

 template <class T> T* myRead5(void * memory, int offset)

 {

     T* t = (T*)((char*)memory+offset);

     return t;

 }

 int main()

 {

     char bytes[] = "\x05\x00\x00\x00\x0A\x00\x00\x00\x06\x00\x00\x00\x0C\x00\x00\x00";

     Person p = myRead<Person>(bytes);  // 调用 Person 拷贝构造

     printf("age = %d, id = %d\n", p.age, p.id);

     Person p2 = myRead2<Person>(bytes);  // 调用 Person 拷贝构造

     printf("age = %d, id = %d\n", p2.age, p2.id);

     Person* p3 = myRead3<Person>(bytes, );

     printf("age = %d, id = %d\n", p3->age, p3->id);

     Person* p4 = new Person;

     myRead4<Person>(bytes, , p4);

     printf("age = %d, id = %d\n", p4->age, p4->id);

     //这个会崩溃

     //Person* p5 = NULL;

     //myRead4<Person>(bytes, 7, p5);

     //printf("age = %d, id = %d\n", p5->age, p5->id);

     Person* p6 = myRead5<Person>(bytes, );

     printf("age = %d, id = %d\n", p6->age, p6->id);

     cin.get();

     return ;

 }

 age = , id =

 age = , id =

 age = , id =

 age = , id =

 //程序崩溃

 age = , id =