c++二进制文件不会自动建立吗

问题遇到的现象和发生背景

做练习题

问题相关代码，请勿粘贴截图

struct emp
{
    int num;
    string name;
    int age;
    float wage;
};
int main()
{
    emp s[7]= { 2101,"Li",34,1203,2104,"Wang",23,674.5,2108,"Fun",54,778,
                  3006,"Xue",45,476.5,5101,"Ling",39,656.6 },s1;
    //ofstream outfile("staf.dat");
    fstream iofile("staf.dat", ios::in | ios::out | ios::binary);
    //iofile.clear();
    if(!iofile)
    {
        cerr << "open staff.dat error!";
        abort();
    }
    int i, m, num;
    cout << "Five staff:" << endl;
    for (i = 0; i < 5; i++)
    {
        cout << s[i].num << ' ' << s[i].name << ' ' << s[i].age << ' ' << s[i].wage << endl;
        iofile.write((char*)&s[i], sizeof(s[i]));
    }
    cout << "please input data you want insert:" << endl;
    for(i=0;i<2;i++)
    {
        cin >> s1.num >> s1.name >> s1.age >> s1.wage;
        iofile.seekp(0, ios::end);
        iofile.write((char*)&s1, sizeof(s1));
    }
    iofile.seekp(0, ios::beg);
    for (i = 0; i < 7; i++)
    {
        iofile.read((char*)&s[i], sizeof(s[i]));
        cout<< s[i].num << ' ' << s[i].name << ' ' << s[i].age << ' ' << s[i].wage << endl;
    }
    bool find;
    cout << "enter number you want search,enter 0 to stop.";
    cin >> num;
    while (num)
    {
        find = false;
        iofile.seekg(0, ios::beg);
        for (i = 0; i < 7; i++)
        {
            iofile.read((char*)&s[i], sizeof(s[i]));
            if (num == s[i].num)
            {
                m = iofile.tellg();
                cout << num << " is No." << i << endl;
                cout << s[i].num << " " << s[i].name << " " << s[i].age << " " << s[i].wage << endl;
                find = true;
                break;
            }
        }
        if (!find)
            cout << "can't find " << num << endl;
        cout << "enter number you want search,enter 0 to stop.";
        cin >> num;
    }
    iofile.close();
    return 0;
}

运行结果及报错内容

Debug error!

我的解答思路和尝试过的方法

刚开始用了clear，不报错了，但是写不了文件，文件依然没有建立。
后来建立文件之后就好了

我想要达到的结果

这个跟| ios::binary没啥关系吧，加了 ios::in就不会自动创建新文件了