C++构造函数实例——拷贝构造，赋值

#define _CRT_SECURE_NO_WARNINGS //windows系统
#include <iostream>
#include <cstdlib>
#include <cstring>
using namespace std;class student
{
private:
char *name;
int age;
public:
student(const char *n = "no name", int a = )
{
name = new char[]; // 比malloc好!
strcpy(name, n);
age = a;
cout << "构造函数，申请了100个char元素的动态空间" << endl;
}
student & operator=(const student &s)
{
strcpy(name, s.name);
age = s.age;
cout << "赋值函数，保证name指向的是自己单独的内存块" << endl;
return *this; //返回 “自引用”
}
student(const student &s)
{ // 拷贝构造函数 Copy constructor
name = new char[];
strcpy(name, s.name);
age = s.age;
cout << "拷贝构造函数，保证name指向的是自己单独的内存块" << endl;
}
void display(void)
{
cout << name << ", age " << age << endl;
}
virtual ~student()
{ // 析构函数
cout << "析构函数，释放了100个char元素的动态空间" << endl;
delete[] name; // 不能用free!
}
};
int main()
{
//student s; //编译错误，类中实现了构造函数，因此，需要有参数
student k("John", );
student mm(k); //拷贝构造函数 student m("lill", );
m.display(); m = k; //赋值函数
k.display();
mm.display(); return ;
}