C++ 从格式化的文本文件中读取“ struct”。
示例
struct info_type
{
std::string name;
int age;
float height;
// we define an overload of operator>> as a friend function which
//授予对私有数据成员的特权访问
friend std::istream& operator>>(std::istream& is, info_type& info)
{
//跳过空格
is >> std::ws;
std::getline(is, info.name);
is >> info.age;
is >> info.height;
return is;
}
};
void func4()
{
auto file = std::ifstream("file4.txt");
std::vector<info_type> v;
for(info_type info; file >> info;) //继续阅读直到我们用完为止
{
//我们只有在读取成功的情况下才能到达这里
v.push_back(info);
}
for(auto const& info: v)
{
std::cout << " name: " <<info.name<< '\n';
std::cout << " age: " <<info.age<< " years" << '\n';
std::cout << "height: " <<info.height<< "lbs" << '\n';
std::cout << '\n';
}
}file4.txt
Wogger Wabbit 2 6.2 Bilbo Baggins 111 81.3 Mary Poppins 29 154.8
输出：
name: Wogger Wabbit age: 2 years height: 6.2lbs name: Bilbo Baggins age: 111 years height: 81.3lbs name: Mary Poppins age: 29 years height: 154.8lbs