c++ - STL vector里面类访问推送

Question

在 Custothe 类中将整数插入 vector 的语法是什么？

class Customer {
vector <int> loyalID;
}

int main {
Customer customer;

vector<Customer>customers;

customers.push_back(/*some integers to go into loyalID vector*/);
}

Answer 1

loyalID 是Customer 的私有(private)字段。要么将其公开(不推荐)，要么添加一个公共(public)方法:

class Customer {
  vector <int> loyalID;

  public:
  void addLoyalId(int id)
  {
    loyalID.push_back(id);
  }
}

访问忠诚 ID:

class Customer {
  vector <int> loyalID;

  public:
  void addLoyalId(int id)
  {
    loyalID.push_back(id);
  }

  std::vector<int>::iterator begin() const { return _loyalID.begin(); }
  std::vector<int>::iterator end() const { return _loyalID.end(); }
}

用法:

Customer c;
c.addLoyalId(1);
c.addLoyalId(2);
c.addLoyalId(3);

for (auto&& id : c)
{
  std::cout << id << " ";
} // will print "1 2 3"