调用CPP构造与重载>>运算

Question

我很新的C++，我想知道，如果以下是可能的：

考虑你有

class Client { 
public: 
    Client(string firstname, string lastname); 
// ... 
} 

你可以重载>>运营商用刚刚输入的输入生成一个新对象？

像

istream& operator>> (istream& is, Client* client) { 
    cout << "First Name: "; 
    is >> client->firstName; 
    cout << "Last Name: "; 
    is >> client->lastName; 
    return is; 
} 

？

什么是正确的方式来创建一个基于用户输入使用重载>>运算符的对象，你会怎么做？ 如果我想这样做，这样，我会写

Client* client; 
cin >> client; 

但在那一刻，客户端已创建...

感谢

Answer 1

你可以像下面这样做（需要通过引用传递客户端的指针，然后读取到临时变量并创建客户端）：

istream& operator >> (istream& is, Client * &client) { 
    string firstname, lastname; 
    cout << "First Name: "; 
    is >> firstname; 
    cout << "Last Name: "; 
    is >> lastname; 
    client = new Client(firstname, lastname); 
    return is; 
} 

Client* client; 
cin >> client; 
// use client 
delete client; 

但我不会建议一般。更清洁的方式是有

istream& operator >> (istream& is, Client &client) { 
    cout << "First Name: "; 
    is >> client.firstname; 
    cout << "Last Name: "; 
    is >> client.lastname; 
    return is; 
} 

Client client; 
cin >> client; 
// use client 
// client destroyed on scope exit