Carrierwave 对不同文件类型的不同大小限制

Carrierwave different size limits for different file types

我有一个允许的文件扩展名列表

def extension_white_list
  %w(pdf doc docx xls xlsx html tif gif jpg jpeg png bmp rtf txt)
end

以及模型中定义的大小限制验证

mount_uploader :inv_file, InvFileUploader

validates_size_of :inv_file, maximum: 25.megabyte, message: "Attachment size exceeds the allowable limit (25 MB)."

它工作正常,大小限制验证应用于所有定义的文件扩展名。

但我想对不同的文件应用不同的大小限制,即

我怎样才能做到这一点?

你可以这样试试

class Product < ActiveRecord::Base 
  mount_uploader  :inv_file, InvFileUploader

  validate :file_size

  def file_size
   extn = file.file.extension.downcase
   size = file.file.size.to_f
   if ["png", "jpg", "jpeg"].include?(extn) && size > 5.megabytes.to_f
     errors.add(:file, "You cannot upload an image file greater than 5MB")
   elsif (extn == "pdf") && size > 20.megabytes.to_f
     errors.add(:file, "You cannot upload an pdf file greater than 20MB")
   else
     errors.add(:file, "You cannot upload a file greater than 25MB")       
   end
 end
end