Question

我尝试使用push将对象添加到数组中。我有一个程序，你可以注册客人。当我从菜单中选择签入选项时，无法将新访客添加到访客历史记录中。

这不起作用：

def self.check_in
    puts "Welcome to the checkin"
    puts "Please state your first name: "
    firstName = gets.chomp
    puts "Please state your last name:"
    lastName = gets.chomp
    puts "Write your address: "
    address = gets.chomp
    puts "and your phone number: "
    phone = gets.chomp
    puts "finally, your arrival date!"
    arrived = gets.chomp

        newPLot = $camping.generateParkingLot
        guest = Guest.new(firstName, lastName, address, phone, arrived)
        $camping.current_guests[newPLot-1] = guest

        puts "The registration was a success!! You have received plot " + newPLot.to_s + "."
        @all_guests.push(guest)   # adds the guest to the history 
  end

这里我得到一个check_in': undefined method推送nil：NilClass（NoMethodError）。但如果我注释掉这一行：

#@all_guests.push(guest)   # adds the guest to the history

我可以注册一位客人。然后，当我从菜单中选择3选项时：

def self.do_action(action)
 # utför händelse baserat på valet
  case action
     when 1:
        check_in
     when 2:
        check_out
     when 3:
       puts $camping.current_guests
      when 4:
       puts $camping.all_guests
      when 5:
       puts "You are now leaving the camping, welcome back!"
       exit    
     end
  end

然后我看到那里的客人。唯一的问题是我不能做4显示所有客人的选项，因为我已经注释掉了这行代码。因此，为了解决这个问题：

@all_guests.push(guest)   # adds the guest to the history

没有收到错误消息??感谢所有的帮助！

Answer 1

@all_guests未在您收到错误的文件中定义，它在$camping全局中定义。将代码更改为

$camping.all_guests.push(...)

并查看这是否适合您。

未定义的方法`push'代表nil：NilClass（NoMethodError）Ruby

1 个答案: