Ruby on rails - 如何使用嵌套模型答案

【问题标题】：Ruby on rails - how to use nested modelsRuby on rails - 如何使用嵌套模型
【发布时间】：2014-07-15 11:14:18
【问题描述】：

我有模特

class Company::Office < ActiveRecord::Base
  ...

  def outcome_loans
    moneys.where(
      "date >= ? AND account_from = ? AND account_to = ?",
      Time.now.beginning_of_day,
      Book::Account.find_by_number('50').id,
      Book::Account.find_by_number('66.1').id
    ).sum(:outcome)
  end

end

当我尝试调用方法“outcome_loans”时，我收到错误“NameError: uninitialized constant Company::Book::Account”

如何告诉 Rails，我想使用“Book::Account”而不是“Company::Book::Account”

【问题讨论】：

标签： ruby-on-rails ruby class nested-class

【解决方案1】：

是的，写成

def outcome_loans
    moneys.where(
      "date >= ? AND account_from = ? AND account_to = ?",
      Time.now.beginning_of_day,
      ::Book::Account.find_by_number('50').id,
      ::Book::Account.find_by_number('66.1').id
    ).sum(:outcome)
end

现在，您将能够在Company::Office 中使用Book 类。

阅读此Ruby: what does :: prefix do?

【讨论】：