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您能否将变量用于铁路参考表栏目?
原标题:Can you use variables to reference table columns in Rails?

我要说的是,我不想改变。 项目1,项目2......25。 我没有掌握栏目名称,而是将Im从中转成更好的结构。

由于命名公约的模式,我可以在传单上设定一栏名称。 问题是,当我试图将我的变数作为目标钥匙时,它就变成了字面,而不是变数的内容。

例如,这项工作:

if !order.item1.empty?
  OrderItem.create(
  :item => order.item1,
  :quantity => order.qty1,
  :price => order.price1
)

但是,我不想逐手作25个改动。

i = 1
while i < 25
    item_ref = "item" + i.to_s
    if !order.item_ref.empty?
    OrderItem.create(
        :item => order.item_ref,
        etc...)
    i += 1
    end
end

当然,这并不奏效。 铁路试图寻找订单。 项目_ref.item1, 确实存在。

我在各种项目上多次打过这个问题,任何想法?

最佳回答

http://www.un.org。 另外,使用<代码>25. 时间(0)或<代码>(1.25).each do >而不是你自己的休息室。

问题回答

我真的会鼓励你使用这种设计,但不管怎么说,你可以采用<代码>send(<>send()。 载于order.send(>item + ito_s”>

try this it works in my case

i = 1
while i < 25
  item_ref = "item" + i.to_s
  unless order[item_ref].empty?
    OrderItem.create :item => order.item_ref,:blah blah ...
    i += 1
 end
end




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