我需要你帮我处理这个代码。 这是一个面包店管理系统，我在将产品添加到文件（一个txt文件）时遇到了问题，每次添加产品时，它只显示产品的名称，其余的都是奇怪的符号，系统无法识别，这也影响了buy（）功能。

  class addProduct{
    char name[100];
    Date product_date, validity;

    public:
        float price, discount, total;
        int number, quantity, day, month, year;
        Date sales_date;
        void add();
        int disc();
        
};

ofstream file;
addProduct product;
addProduct quant;

void addProduct::add(){
            cout<<"Please enter the product name: ";
            cin.ignore();
            cin.getline(name, 100);
            cout<<"Please enter the product number: ";
            cin>>number;
            cout<<"Please enter the product quantity: ";
            cin>>quantity;
            cout<<"Please enter the price: ";
            cin>>price;
            cout<<"Please enter the discount(%): ";
            cin>>discount;
            cout<<"Please enter the product date(day, month, year): ";
            product_date.enter();
            cout<<"Please enter the validity(day, month, year): ";
            validity.enter();
}

int addProduct::disc(){
    discount = (price*discount)/100;
    total = price - discount;
    return total;
}

void add_product(){
    ofstream file;
    file.open("BakeSale2.txt", ios::app);
    product.add();
    file.write((char*)&product,sizeof(addProduct));
    file.close();
}

输出