C++中的类型转换与STL标准模板库

一、C++类型转换

在C++中类型转换包含 static_cast、const_cast、dynamic_cast、reinterpret_cast 四种类型转换。使用原始类型转换,所有转换都是一种写法,可读性不高,有可能有潜在的风险

1、static_cast

该类型转换函数用于不同类型的属性之间的转换

#include <iostream>
using namespace std;


void* func(){
    int i = 0;
    return &i;
}
void main(){
    //自动类型转换
    //int i = 0;
    //double d = i;
    //或
    //double d = 9.5;
    //int i = d;
    
    // int i = 8;
    // double d = 9.5;
    // i = static_cast<int>(d);
    // cout << "i = " << i << endl;
    
    int i = 9;
    int *i_p = &i;
}

void* 转 char*

void* func(int type){
    switch(type){
        case 1:
            int i = 11;
            return &i;
        case 2:
            int a = 'X';
            return &a;
        default:
            return NULL;
    }
}
void main(){
   //void* 转 char*
   //char* c_p = (char*)func(2);
   char* c_p = static_cast<char*>(func(2));
   
   //C++
   
   func
   //C
}

2、const_cast

该类型转换函数用于去常量,一般使用在常量属性转为非常量属性时使用

void func(char c[]){
    //可以修改
    c[0] = 'H';
    c[1] = 'a';
}

void func2(const char c[]){
    //c[0] = 'H'; //不能修改
    //c[1] = 'a';//不能修改
    //通过指针间接赋值
    //其他人并不知道,这次转型是为了去常量
    //char* c_p = (char*)c;
    //c_p[1] = 'a';
    //cout << c << endl;
    
    //C++ 去常量,可读性高
    char* c_p = const_cast<char*>(c);
    c_p[1] = 'y';
    cout << c << endl;
}

void main(){
    char c[] = "hello";
    func2(c);
    
    getchar();
}

3、dynamic_cast

该类型转换用于父类对象转换为子类时使用,处理父类转为子类时的不确定性(类型不匹配时转型失败,返回NULL)

class Person{
public:
    virtual void print(){
        cout << "人" <<endl;
    }    
};

class Man : public Person{
public:
    void print(){
        cout << "男人" <<endl;
    }
    void smoking(){
        cout << "吸烟" <<endl;
    }
};

class Woman : public Person{
public:
    void print(){
        cout << "女人" <<endl;
    }
    void makeup(){
        cout << "化妆" <<endl;
    }
};

void func(Person* obj){
    obj->print();
    //调用子类的特有函数,需要转为实际类型
    //当传入Woman对象时,转型为Man,转型失败,但是编译器并为察觉
    //Man* man = (Man*)obj;
    //man->print();
      
    //转型失败,返回NULL  
   //Man* man = dynamic_cast<Man*>(obj);
    //man->print();
    Man* man = dynamic_cast<Man*>(obj);
    if(man!=NULL){
        man->smoking();
    }
    
    Woman* woman = dynamic_cast<Woman*>(obj);
    if(woman!=NULL){
        woman->makeup();
    }
    
    
}
void main(){
    Woman w1;
    //父类类型的指针指向子类对象
    Person* p = &w1;
    func(p);
    
    getchar();
}

4、reinterpret_cast

该类型转换用于函数指针之间的转型,在使用函数指针转型时使用

void func1(){
    
}

char* func2(){
    return "abc";
}

typedef void(*f_p)();

void main(){
    f_p f_array[6];
    f_array[0] = func1;
    //C 方式
    f_array[1] = (f_p)func2;
    f_array[1] = reinterpret_cast<f_p>func2;

    
    getchar();
}

二、IO 流

在 C++ 中,通过 头文件中的 ifstream 读取文件,ofstream 写入文件,完成 IO 流操作

1、文本文件操作

对于文本文件,可进行使用 ifstream 中的 get(ch) 读取一个字符;使用 fout << 写入一个字符串


#include <fstream>
void main(){
    char fname[] = "D://dest.text";
    //输出流
    ofstream fout(fname);
    //创建失败
    if(fout.bad()){
        return -1;
    }
    fout << "Jack" << endl;
    fout << "Rose" << endl;
    fout.close();
    
    //读取
    ifstream fin(fname);
    if(fin.bad()){
        return -2;
    }
    char ch;
    while(fin.get(ch)){
        cout << ch;
    }
    fin.close();
}

2、二进制文件操作

对于二进制文件,可进行使用 ifstream中的read(buff,1024) 读取二进制文件,通过 ofstream中的write(buff,1024) 写入到对应文件中


#include <fstream>
void main(){
    char src[] = "D://xueshan.jpg";
    char src_copy[] = "D://xueshan_copy.jpg";
     //读取
    ifstream fin(src,ios::binary);
    
    //输出流
    ofstream fout(src_copy,,ios::binary);
    //创建失败
    if(fin.bad()||fout.bad()){
        return -1;
    }
    while(!fin.eof()){
        char buff[1024] = {0};
        fin.read(buff,1024);
        //写入
        fout.write(buff, 1024);
    }
    //关闭
    fin.close();
    fout.close();
}

3、对象持久化

class Person{
private:
    char* name;
    int age;
public:
    Person(){}
    Person(char* name,int age){
        this->name = name;
        this->age = age;
    }
    
    char* getName(){
        return this->name;
    }
    
    int getAge(){
        return this->age;
    }
    
    void print(){
        cout << this->name << "," << this->age << endl;
    }
};

void main(){
    Person p1(const_cast<char*>("Jack"),25);
    Person p2(const_cast<char*>("Rose"),22);
    //输出流
    ofstream fout("D://c_obj.data",ios::binary);
    //指针能够读取到正确的数据,读取内存区的长度
    fout.write((char*)(&p1), sizeof(Person));
    fout.write((char*)(&p2), sizeof(Person));
    fout.close();
    
    //输入流
    ifstream fin("D://c_obj.data",ios::binary);
    Person tmp;
    fin.read((char*)(&tmp), sizeof(Person));
    tmp.print();
    
    fin.read((char*)(&tmp), sizeof(Person));
    tmp.print();
}

三、STL(standard template library)标准模板库

在 C++ 中包含很多标准模板库,可以让代码更加简洁

1、string 模板库

使用 string 模板库,在边写代码时更改简洁易用,但是在JNI中 string 需要转为 char ,,在转为jstring返回*

1.1 string 初始化

#include <string>
void main(){
    string s1 = "Hello ";
    string s2(" every day");
    string s3 = s1 + s2;
    cout << s3 << endl;
    
    //string 转 c 字符串,在JNI中要转为C的str 然后再转为jstring返回
    const char* c_str = s1.c_str();
    cout << c_str << endl;
}

1.2 string 遍历

#include <string>
//string遍历
void main()
{
	string s1 = "craig david";
	//			 ^
	//1 数组方式
	for (int i = 0; i < s1.length(); i++)
	{
		cout << s1[i] << endl;
	}
	//2 迭代器指针
	for (string::iterator it = s1.begin(); it != s1.end(); it++)
	{
		cout << *it << " ";
	}
	cout << endl;
	//3 at函数(charAt)
	// 可能会抛出异常
	try
	{
		for (int i = 0; i < s1.length() + 3; i++)
		{
			cout << s1.at(i) << " ";
		}
	}
	catch (...)
	{
		cout << "异常" << endl;
	}


	system("pause");
}

1.3 string 字符串查找替换

#include <string>
#include <iostream>

using namespace std;
//字符串查找替换
void main()
{
	string s1 = "apple google apple iphone";
	//从0开始查找"google"的位置
	int idx = s1.find("google", 0);
	cout << idx << endl;

	//统计apple出现的次数
	int idx_app = s1.find("apple",0);
	//npos大于任何有效下标的值
	int num = 0;
	while (idx_app != string::npos)
	{
		num++;
		cout << "找到的索引:" << idx_app << endl;
		idx_app+=5;
		idx_app = s1.find("apple", idx_app);
	}

	cout << num << endl;
	system("pause");
}

1.4 string 删除(截取)和插入

#include <string>
#include <iostream>

using namespace std;
//删除(截取)和插入
void main()
{
	string s1 = "apple google apple iphone";
	//删除a,找到a所在的指针
	string::iterator it = find(s1.begin(),s1.end(),'g');
	//只能删除一个字符
	s1.erase(it);
	
	//开头末尾插入字符串
	s1.insert(0, "macos");
	s1.insert(s1.length(), " facebook");

	cout << s1 << endl;
	system("pause");
}

1.5 string 大小写转换

#include <string>
#include <iostream>
#include <algorithm> //算法

using namespace std;
//java StringBuffer才可变
//String 不可变
//大小写转换
void main()
{
	string s1 = "JASON";
	//原始字符串的起始地址,原始字符串的结束地址, 目标字符串的起始地址, 函数名称
	transform(s1.begin(), s1.end()-1,s1.begin(), tolower);
	cout << s1 << endl;


	transform(s1.begin(), s1.end() - 1, s1.begin(), toupper);
	cout << s1 << endl;

	system("pause");
}

2、容器 vector 模板库

使用 vector 模板库,不需要使用动态内存分配,就可以使用动态数组

2.1 vector 初始化与遍历

#include <vector>

void printVector(vector<int> &v)
{
	//通过数组的方式遍历
	for (int i = 0; i < v.size(); i++)
	{
		cout << v[i] << endl;
	}
}


void main(){
    //动态数组
    vector<int> v;
    v.push_back(12);
    v.push_back(118);
    v.push_back(1);
    v.push_back(52);
    v.push_back(20);
    //遍历
    for(int i = 0; i<v.size(); i++){
        cout << v[i] << endl;
    }
    
    //部分复制
	vector<int> v3(v1.begin(),v1.begin()+2);
	 for(int i = 0; i<v3.size(); i++){
        cout << v3[i] << endl;
    }
    
}

2.2 vector 添加和删除

//添加 删除
void main()
{
	//添加到结尾
	vector<int> v1;
	v1.push_back(20);
	v1.push_back(40);
	v1.push_back(15);
	v1.push_back(7);

	//访问头部
	v1.front() = 11;
	//访问尾部
	v1.back() = 90;

	//删除结尾的元素
	//v1.pop_back();
	while (v1.size() > 0)
	{
		cout << "末尾的元素:" << v1.back() << endl;
		v1.pop_back();
	}

	printVector(v1);

	system("pause");
}

2.3 vector 数组方式

//数组的方式
void main()
{
	vector<int> v1;
	v1.push_back(20);
	v1.push_back(40);
	v1.push_back(15);
	v1.push_back(7);

	v1[2] = v1[2] +10;

	//容器等价于动态数组	
	vector<int> v2(10);
	for (int i = 0; i < v2.size(); i++)
	{
		v2[i] = i + 1;
	}

	printVector(v2);

	system("pause");
}

2.4 vector 迭代器遍历

//迭代器遍历
//迭代器的种类(正向,反向迭代器)
void main()
{
	vector<int> v1;
	v1.push_back(20);
	v1.push_back(40);
	v1.push_back(15);
	v1.push_back(7);
	//正向
	for (vector<int>::iterator it = v1.begin(); it < v1.end(); it++)
	{
		cout << *it << endl;
	}
	cout << "-----------------" << endl;
	//反向迭代
	for (vector<int>::reverse_iterator it = v1.rbegin(); it < v1.rend(); it++)
	{
		cout << *it << endl;
	}

	system("pause");
}

2.5 vector 插入和删除

void main()
{
	vector<int> v1(10);
	for (int i = 0; i < v1.size(); i++)
	{
		v1[i] = i + 1;
	}

	//删除指定位置
	vector<int>::iterator it = v1.begin();
	it += 3;
	v1.erase(it);

	//distance(v1.begin(), it);

	//删除区间
	v1.erase(v1.begin(), v1.begin() + 3);

	for (vector<int>::iterator it = v1.begin(); it < v1.end(); it++)
	{
		if (*it == 5)
		{		
			printf("%x\n", it);
			vector<int>::iterator tmp = v1.erase(it); //注意以后开发中编译器版本问题
			printf("%x,%x\n",it,tmp);
		}
	}

	//插入
	v1.insert(v1.begin() + 2, 100);
	v1.insert(v1.end() - 1, 200);

	printVector(v1);

	system("pause");
}

3、队列 deque 模板库

3.1 双向队列


//双向队列
#include <deque>
void printDeque(deque<int>& q)
{
	for (int i = 0; i < q.size(); i++)
	{
		cout << q[i] << endl;
	}
}


void main()
{
	deque<int> d1;
	//添加到尾部
	d1.push_back(2);
	d1.push_back(10);
	//添加到头部
	d1.push_front(-90);
	d1.push_front(-30);

	//printDeque(d1);

	//cout << d1.front() << endl;
	//cout << d1.back() << endl;

	//两个方向弹出
	//d1.pop_back();
	//d1.pop_front();

	printDeque(d1);

	//查找第一个-90元素索引位置,无需遍历
	deque<int>::iterator it = find(d1.begin(), d1.end(), -90);
	if (it != d1.end())
	{
		int idx = distance(d1.begin(), it);
		cout << "索引位置为:" << idx << endl;
	}


	system("pause");
}

3.2 没有迭代器的队列

#include <iostream>
#include <queue>
using namespace std;
void main()
{
	queue<int> q;
	q.push(78);
	q.push(18);
	q.push(20);
	q.push(33);
	
	//q.front();
	//q.back();
	while (!q.empty())
	{
		int tmp = q.front();
		cout << tmp << endl;
		q.pop();
	}	
	system("pause");
}

3.3 优先级队列

#include <iostream>
#include <queue>
using namespace std;
void main()
{
	//默认 最大值优先级
	priority_queue<int> pq1;
	pq1.push(12);
	pq1.push(3);
	pq1.push(40);
	pq1.push(15);

	while (!pq1.empty())
	{
		int tmp = pq1.top();
		cout << tmp << endl;
		pq1.pop();
	}

	cout << "----------" << endl;
	//最小值优先级队列
	priority_queue<int, vector<int>, greater<int>> pq2;
	pq2.push(12);
	pq2.push(3);
	pq2.push(40);
	pq2.push(15);

	while (!pq2.empty())
	{
		int tmp = pq2.top();
		cout << tmp << endl;
		pq2.pop();
	}

	system("pause");
}

4、stack 栈 模板

4.1 stack 栈的初始化


#include <iostream>
#include <stack>

using namespace std;

void main()
{
	stack<int> s;
	for (int i = 0; i < 10; i++)
	{
		s.push(i + 1);
	}

	while (!s.empty())
	{
		int tmp = s.top();
		cout << tmp << endl;
		s.pop();
	}

	system("pause");
}

5、list 模板

5.1 list 初始化


#include <iostream>
#include <list>

using namespace std;

void printList(list<int>& lst)
{
	//迭代器
	//没有重载“<”运算符
	for (list<int>::iterator it = lst.begin(); it != lst.end(); it++)
	{
		cout << *it << endl;
	}
}
//基本操作
/*
void main()
{
	list<int> lst;
	for (int i = 0; i < 10; i++)
	{
		//尾部插入元素
		lst.push_back(i);
	}

	//头部插入元素
	lst.push_front(80);
	lst.push_front(90);

	list<int>::iterator it = lst.begin();
	it++;
	cout << *it << endl;
	//it = it + 3; 注意:不支持随机访问		

	printList(lst);

	system("pause");
}

5.2 list 插入


#include <iostream>
#include <list>

using namespace std;

void main()
{
	list<int> lst;
	for (int i = 0; i < 10; i++)
	{
		//尾部插入元素
		lst.push_back(i);
	}

	list<int>::iterator it = lst.begin();
	it++;
	lst.insert(it, 100);

	printList(lst);
	system("pause");
}

5.3 list 初始化


#include <iostream>
#include <list>

using namespace std;

void main()
{
	list<int> lst;
	for (int i = 0; i < 10; i++)
	{
		//尾部插入元素
		lst.push_back(i);
	}

	list<int>::iterator it = lst.begin();
	//删除
	it++;
	//删除第二个元素
	//lst.erase(it);

	//删除区间(已经被删除了元素不能再删除)
	list<int>::iterator it_begin = lst.begin();
	list<int>::iterator it_end = lst.begin();
	it_end++;
	it_end++;
	it_end++;
	lst.erase(it_begin, it_end);

	//直接根据内容删除元素
	lst.remove(5);

	printList(lst);

	system("pause");
}

6、set 模板

6.1 set 初始化

#include <iostream>
#include <set>

using namespace std;

//set 元素唯一 默认从小到大
void printSet(set<int> &s)
{
	for (set<int>::iterator it = s.begin(); it != s.end(); it++)
	{
		cout << *it << endl;
	}
}

void main()
{
	set<int> s;
	//添加元素
	for (int i = 0; i < 10; i++)
	{
		s.insert(i+1);
	}
	s.insert(20);
	s.insert(15);
	s.insert(15);

	//删除
	set<int>::iterator it = s.begin();
	it++;
	s.erase(it);	

	printSet(s);
	system("pause");
}

6.2 set 元素按照从大到小排列

#include <iostream>
#include <set>
#include <functional>
using namespace std;

void main()
{
	//同Java中:Map<String,List<String>> 
	set<int,greater<int>> s;
	s.insert(10);
	s.insert(5);
	s.insert(20);
	s.insert(99);

	for (set<int,greater<int>>::iterator it = s.begin(); it != s.end(); it++)
	{
		cout << *it << endl;
	}

	system("pause");
}

6.3 set 自定义排序规则

#include <iostream>
#include <set>
#include <functional>
using namespace std;

//元素类型为Teacher对象,按照年龄排序

class Teacher
{
public:
	Teacher(char* name, int age)
	{
		this->name = name;
		this->age = age;
	}

	void print()
	{
		cout << name << "," << age << endl;
	}

public:
	char* name;
	int age;
};

//自定义排序规则
//仿函数
struct MyAgeSorter
{
	bool operator()(const Teacher &left, const Teacher &right)
	{
		return left.age < right.age;
	}
};

void main()
{
	set<Teacher, MyAgeSorter> s;
	s.insert(Teacher(const_cast<char*>("jack"),18));
	s.insert(Teacher(const_cast<char*>("rose"), 20));
	s.insert(Teacher(const_cast<char*>("jason"), 22));
	s.insert(Teacher(const_cast<char*>("alan"), 5));
	//s.insert(Teacher("jimy", 5)); //不会插入

	for (set<Teacher>::iterator it = s.begin(); it != s.end(); it++)
	{
		cout << (*it).name << "," << (*it).age << endl;
	}

	system("pause");
}

6.3 set 查找

#include <iostream>
#include <set>
using namespace std;

void main()
{
	set<int> s;
	//添加元素
	for (int i = 0; i < 10; i++)
	{
		s.insert(i + 1);
	}

	//printSet(s);

	//等于4的元素指针
	set<int>::iterator s_4 = s.lower_bound(4); 
	//cout << *s_4 << endl;
	//大于4的元素指针
	set<int>::iterator s_5 = s.upper_bound(4);
	//cout << *s_5 << endl;

	//一次性获取等于4的元素指针,和大于4的元素指针\
	//BasicNameValuePair
	pair<set<int>::iterator, set<int>::iterator> p = s.equal_range(4);
	cout << *p.first << endl;
	cout << *p.second << endl;
	system("pause");
}

6.4 multiset 允许重复的元素

#include <iostream>
#include <set>
using namespace std;
void main()
{
	multiset<int> s;
	s.insert(2);
	s.insert(8);
	s.insert(2);
	s.insert(8);

	for (multiset<int>::iterator it = s.begin(); it != s.end(); it++)
	{
		cout <<  *it << endl;
	}

	system("pause");
}

7、map 模板

7.1 map 初始化

#include <iostream>
#include <map>
#include <string>
using namespace std;

void main()
{
	//key -> value
	//1.
	map<int, string> map1;
	map1.insert(pair<int, string>(1, "jack"));
	map1.insert(pair<int, string>(2, "rose"));

	//2
	map1.insert(make_pair(3, "jason"));

	//3
	map1.insert(map<int, string>::value_type(4, "alan"));

	//4
	map1[5] = "jimmy"; //map["NO1"] = 90;

	//前三种方式,如果key已经存在,重复添加会报错
	//第四种方式,如果key已经存在,重复添加会覆盖

	//遍历输出
	for (map<int, string>::iterator it = map1.begin(); it != map1.end(); it++)
	{
		cout << it->first << "," << it->second << endl;
	}


	system("pause");
}

7.2 map 删除元素的方式

#include <iostream>
#include <map>
#include <string>
using namespace std;

void printMap(map<int, string> &map1)
{
	for (map<int, string>::iterator it = map1.begin(); it != map1.end(); it++)
	{
		cout << it->first << "," << it->second << endl;
	}
}

void main()
{
	map<int, string> map1;
	map1.insert(pair<int, string>(1, "jack"));
	map1.insert(pair<int, string>(2, "rose"));
	map1.insert(pair<int, string>(3, "jason"));	

	map<int, string>::iterator it = map1.begin();
	it++;
	map1.erase(it);

	printMap(map1);

	system("pause");
}

7.3 map 添加元素的结果

#include <iostream>
#include <map>
#include <string>
using namespace std;

void main()
{
	map<int, string> map1;
	map1.insert(pair<int, string>(1, "jack"));
	map1.insert(pair<int, string>(2, "rose"));
	map1.insert(pair<int, string>(3, "jason"));
	//获取添加的结果(first元素指针,second 是否成功)
	pair<map<int, string>::iterator, bool> res = map1.insert(pair<int, string>(3, "alan"));
	if (res.second)
	{
		cout << "添加成功" << endl;
	}
	else
	{
		cout << "添加失败" << endl;
	}

	printMap(map1);

	system("pause");
}

7.3 map 查找

#include <iostream>
#include <map>
#include <string>
using namespace std;

void main()
{
	map<int, string> map1;
	map1.insert(pair<int, string>(1, "jack"));
	map1.insert(pair<int, string>(2, "rose"));
	map1.insert(pair<int, string>(3, "jason"));	

	printMap(map1);

	cout << "---------" << endl;

	//获取key等于大于5的元素的值
	pair<map<int, string>::iterator, map<int, string>::iterator> p = map1.equal_range(2);
	if (p.first != map1.end()){
		//等于2的元素key value
		cout << p.first->first << p.first->second << endl;

		//大于2的元素key value
		cout << p.second->first << p.second->second << endl;
	}

	system("pause");
}

7.3 multimap

#include <iostream>
#include <map>
#include <string>
using namespace std;

//一个key对应多个value
//一个部门多个员工
//multimap

class Employee
{
public:
	Employee(char* name,int age)
	{
		this->name = name;
		this->age = age;
	}

public:
	char* name;
	int age;
};

void main()
{
	multimap<string, Employee> map1;

	//开发部
	map1.insert(make_pair("开发", Employee(const_cast<char*>("搁浅"), 20)));
	map1.insert(make_pair("开发", Employee(const_cast<char*>("彪哥"), 20)));

	//财务
	map1.insert(make_pair("财务", Employee(const_cast<char*>("小颖"), 16)));
	map1.insert(make_pair("财务", Employee(const_cast<char*>("rose"), 20)));

	//销售
	map1.insert(make_pair("销售", Employee(const_cast<char*>("阿呆"), 30)));
	map1.insert(make_pair("销售", Employee(const_cast<char*>("呵呵"), 30)));

	//遍历输出
	for (multimap<string, Employee>::iterator it = map1.begin(); it != map1.end(); it++)
	{
		cout << it->first << "," << it->second.name  << "," << it->second.age << endl;
	}

	cout << "----------------" << endl;
	//只获取“财务”部的员工
	//获取“财务部”员工的个数,key对应的value的个数
	int num = map1.count("财务");
	multimap<string, Employee>::iterator it = map1.find("财务");
	int c = 0; //控制循环的次数
	while (it != map1.end() && c < num)
	{
		cout << it->first << "," << it->second.name << "," << it->second.age << endl;
		it++;
		c++;
	}

	system("pause");
}

8、深拷贝与浅拷贝

#include <iostream>
#include <map>
#include <string>
#include <vector>

using namespace std;

class Employee
{
public:
	//构造函数
	Employee(char* name, int age)
	{
		this->name = new char[strlen(name) + 1];
		strcpy(this->name, name);
		this->age = age;
	}

	//析构函数
	~Employee()
	{
		if (this->name != NULL)
		{
			delete[] this->name;
			this->name = NULL;
			this->age = 0;
		}
	}
	//拷贝构造函数
	//Employee e = 
	Employee(const Employee &obj)
	{
		this->name = new char[strlen(obj.name) + 1];
		strcpy(this->name, obj.name);
		this->age = obj.age;
	}

	//重载=
	//e1 = e2;
	Employee& operator=(const Employee &obj)
	{
		//释放旧的内存
		if (this->name != NULL)
		{
			delete[] this->name;
			this->name = NULL;
			this->age = 0;
		}

		//重新分配
		this->name = new char[strlen(obj.name) + 1];
		strcpy(this->name, obj.name);
		this->age = obj.age;

		return *this;
	}

public:
	char* name;
	int age;
};

void func()
{
	vector<Employee> v1;
	Employee e1(const_cast<char*>("jack"), 20);
	v1.push_back(e1);
}

void main()
{
	//vector<Employee> v1;
	//Employee e1("jack",20);
	//将e1拷贝到vector中
	//v1.push_back(e1);

	func();

	system("pause");
}