Question

我如何将<vector>用于对象数组，需要通过构造函数给出值？例如，带有名称的类，年龄需要通过构造函数Student(string n, int a ) { name = n , age = a }获取信息。

所有数据都将通过键盘提供..

Answer 1

这是一个程序的示例代码，能够使用向量获取和存储学生列表的名称和年龄。之后，它打印存储的信息。我使用MSVC作为编译器，所以如果你不在Windows上，你可以删除system("pause")：

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

using namespace std;

class Student {
public:
    Student(string n, int a) : name(n), age(a) {}

    string GetName(void) { return name; }
    int GetAge(void) { return age; }

private:
    string name;
    int age;

};

int main(void) {
    vector<Student> students;

    unsigned int n;

    cout << "How many students are there?" << endl;
    cin >> n;

    for (unsigned int i = 0; i < n; ++i) {
        string name;
        int age;

        cout << endl << "Please give me the information of the student " << i + 1 << endl;

        cout << "What is the name of the student?" << endl;
        cin >> name;

        cout << "What is the age of the student?" << endl;
        cin >> age;

        students.push_back(Student(name, age));
    }

    cout << endl << "Printing information of the students" << endl << endl;

    for (unsigned int i = 0; i < n; ++i) {
        Student& student = students[i];

        cout << "Student " << i + 1 << " is " << student.GetName() << " and is " << student.GetAge() << " years old." << endl;
    }

    system("pause");

    return 0;
}

Answer 2

可以使用initializer-list直接构建vector名学生：

std::vector<Student> students{
    { "John", 22 },
    { "Melissa", 19 }
};

要稍后添加学生，可以使用成员函数emplace_back()，它只是将其参数转发给Student构造函数：

students.emplace_back( "Andy", 23 );

Pre C ++ 11必须使用成员函数push_back()：

students.push_back( Student( "Andy", 23 ) );

可以在链接的参考页面上找到更多用法示例。

如何将<vector>与构造函数一起使用

2 个答案: