奇怪的ifstream行为(Weird ifstream behaviour)

 编写代码将对象写入文件，读取它们并在屏幕上打印 
 
#include<iostream>
#include<fstream>
#include<cstring>
using namespace std;
////////////////////////////////////////////////////////////
class employee{
    private:
        string name;
        unsigned long ID;
    public:
        employee():name(""),ID(0){}
        void putdata(){cout<<"Enter employee's name: ";cin>>name;cout<<"Enter employee's ID: ";cin>>ID;}
        void getdata(){cout<<"Employee's name is: "<<name<<endl;cout<<"Employee's ID is: "<<ID<<endl;}
        friend ostream& operator << (ostream&,employee&);
        friend istream& operator >> (istream&,employee&);
};

ostream& operator << (ostream& f,employee& emp){ // запись объекта в файл
    f<<emp.ID<<"-"<<emp.name<<"?";
    return f;
}

istream& operator >> (istream& f,employee& empl){ // чтение объекта из файла
    char dummy;
    f>>empl.ID>>dummy;
    f>>dummy;
    empl.name="";
    while(dummy!='?'){
        empl.name+=dummy;
        f>>dummy;       
    }
}
////////////////////////////////////////////////////////////
int main(){
    char ch='y';
    ofstream file1;
    ifstream file2;
    file1.open("TAB.txt");
    employee one;
    while(ch=='y'){ // цикл для записи
        one.putdata();
        file1<<one; // write data into file
        cout<<"Go on?(y,n): ";cin>>ch;
    }
    file1.close();
    file2.open("TAB.txt");
    while(file2.good()){ // цикл для чтения из файла
        file2>>one;
        one.getdata();      
    }
    file2.close();
    system("pause");
    return 0;
}
 
 输入对象后，程序将它们打印出来并挂起。 我想while（file2.good（））有问题，但我不确定。 谁有人评论？ 

Writing code to write object into a file, read them, and print on the screen
 
#include<iostream>
#include<fstream>
#include<cstring>
using namespace std;
////////////////////////////////////////////////////////////
class employee{
    private:
        string name;
        unsigned long ID;
    public:
        employee():name(""),ID(0){}
        void putdata(){cout<<"Enter employee's name: ";cin>>name;cout<<"Enter employee's ID: ";cin>>ID;}
        void getdata(){cout<<"Employee's name is: "<<name<<endl;cout<<"Employee's ID is: "<<ID<<endl;}
        friend ostream& operator << (ostream&,employee&);
        friend istream& operator >> (istream&,employee&);
};

ostream& operator << (ostream& f,employee& emp){ // запись объекта в файл
    f<<emp.ID<<"-"<<emp.name<<"?";
    return f;
}

istream& operator >> (istream& f,employee& empl){ // чтение объекта из файла
    char dummy;
    f>>empl.ID>>dummy;
    f>>dummy;
    empl.name="";
    while(dummy!='?'){
        empl.name+=dummy;
        f>>dummy;       
    }
}
////////////////////////////////////////////////////////////
int main(){
    char ch='y';
    ofstream file1;
    ifstream file2;
    file1.open("TAB.txt");
    employee one;
    while(ch=='y'){ // цикл для записи
        one.putdata();
        file1<<one; // write data into file
        cout<<"Go on?(y,n): ";cin>>ch;
    }
    file1.close();
    file2.open("TAB.txt");
    while(file2.good()){ // цикл для чтения из файла
        file2>>one;
        one.getdata();      
    }
    file2.close();
    system("pause");
    return 0;
}
 
After entering objects, th program print them out and hanging. I guess there is a problem with while(file2.good()) but I'm not sure. Can anyone comment?

原文：https://stackoverflow.com/questions/36036223