错误:尝试调用私有方法

Question

来自C风格语法的悠久历史,现在正在尝试学习Ruby(在Rails上),我一直在用它的成语等问题分享我的问题,但今天我遇到了一个我没想到会出现问题的问题.我无法看到任何必须在我面前的东西.

我有一个二进制类,其中包含一个私有方法,用于从路径值派生URI值(uri和路径是类的属性).我打电话self.get_uri_from_path()从内部Binary.upload(),但我得到:

Attempt to call private method

该模型的片段如下所示:

class Binary < ActiveRecord::Base
  has_one :image

  def upload( uploaded_file, save = false )
    save_as = File.join( self.get_bin_root(), '_tmp', uploaded_file.original_path )

    # write the file to a temporary directory
    # set a few object properties

    self.path   = save_as.sub( Rails.root.to_s + '/', '' )
    self.uri    = self.get_uri_from_path()
  end

  private

  def get_uri_from_path
    return self.path.sub( 'public', '' )
  end
end

我打电话不正确吗？我错过了一些更基本的东西吗？目前唯一Binary.get_uri_from_path()被调用的地方是 - Binary.upload().我希望能够在同一个类中调用私有方法,除非Ruby做了与我使用的其他语言明显不同的东西.

谢谢.

Answer 1

不要这样做

self.get_uri_from_path()

做

get_uri_from_path()

因为...

  class AccessPrivate
    def a
    end
    private :a # a is private method

    def accessing_private
      a              # sure! 
      self.a         # nope! private methods cannot be called with an explicit receiver at all, even if that receiver is "self"
      other_object.a # nope, a is private, you can't get it (but if it was protected, you could!)
    end
  end

通过