Ruby-on-rails 在视图中显示 Carrierwave 文件名

Displaying a Carrierwave filename in the view

提问by Chris Alley

I am trying to display the filename of a Carrierwave attachment in a Rails erb template. The following does not work:

我正在尝试在 Rails erb 模板中显示 Carrierwave 附件的文件名。以下不起作用：

<%= @page.form.filename %>

This seems in line with the documentation. Is some additional step needed?

这似乎与文档一致。是否需要一些额外的步骤？

My page model looks like this:

我的页面模型如下所示：

class Page < ActiveRecord::Base

  mount_uploader :form, FormUploader

end

The form uploader looks like this:

表单上传器如下所示：

class FormUploader < CarrierWave::Uploader::Base

  storage :file

  def store_dir
    "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
  end

  def extension_white_list
    %w(pdf)
  end

end

回答by kikito

I have been able to get the filename via the fileinternal parameter:

我已经能够通过file内部参数获取文件名：

<%= @page.form.file.filename %>

回答by Zachary Anker

The documentation you're looking at is the sanitized file, it's what it uses for actually storing a file. The part you're looking for is FormUploader, which is an Uploader, and part of http://rubydoc.info/gems/carrierwave/0.5.2/CarrierWave/Uploader

您正在查看的文档是经过消毒的文件，它用于实际存储文件。您正在寻找的部分是 FormUploader，它是一个上传器，以及http://rubydoc.info/gems/carrierwave/0.5.2/CarrierWave/Uploader 的一部分

If you want to get the file name, you could either read it from the database column directly, or use File.basename(@page.form.path)to extract it easily.

如果要获取文件名，可以直接从数据库列中读取，也可以使用File.basename(@page.form.path)轻松提取。

回答by epylinkn

The Carrierwave docsmight be a bit off, but recommended way seems to be:

该Carrierwave文档可能有点过，但建议的方式似乎是：

@page.form.file.identifier

回答by omarvelous

@adamonduty's solution is great. Another solution I used before, just create a method on the model:

@adamonduty 的解决方案很棒。我之前使用的另一个解决方案，只需在模型上创建一个方法：

def name
  file.path.split("/").last
end

回答by skplunkerin

You're right @epylinkn. Documentation points towards using:

你是对的@epylinkn。文档指向使用：

@page.form.file.identifier

But when I use that, I always get nil(just as @Cheng commented).

但是当我使用它时，我总是得到nil（就像@Cheng 评论的那样）。

I then inspected my objects methods (@page.form.file.methods.inspect), and found the following to work:

然后我检查了我的对象方法 ( @page.form.file.methods.inspect)，并发现以下方法有效：

@page.form.file_identifier

回答by Solomons_Ecclesiastes

In your model's associated uploader class, define a filename method.

在模型的关联上传器类中，定义文件名方法。

def filename
  File.basename(path)
end

You can then call

然后你可以打电话

model_instance.file.filename

Works as of CarrierWave 1.1.0. This is a succinct restatement/amalgamation of kikito and Chris Alley's responses above.

从 CarrierWave 1.1.0 开始工作。这是上面 kikito 和 Chris Alley 回答的简洁重述/合并。

回答by adamlamar

If you're using ActiveRecord, you can directly access the field named formin two ways:

如果您使用的是 ActiveRecord，则可以通过form两种方式直接访问命名字段：

def my_method
  self[:form]
end

or

或者

def my_method
  form_before_type_cast
end

The second method is read-only.

第二种方法是只读的。

回答by Winfield

I'm assuming you've got models like this?

我假设你有这样的模型？

class Page
  mount_uploader :form, FormUploader
end

If so you should be able to call:

如果是这样，您应该可以调用：

@page.form.url
@page.form.filename

Are you sure you've uploaded/attached the file correctly? What do you see when you inspect @page.form? Remember, the attachment will not be saved until you've fully processed the upload.

您确定您已正确上传/附加文件吗？当您检查@page.form 时，您看到了什么？请记住，在您完全处理完上传之前，不会保存附件。

回答by deefour

CarrierWave::SanitizedFilehas a private original_filenamemethod containing the filename of the uploaded file. (docs: http://rdoc.info/github/jnicklas/carrierwave/master/CarrierWave/SanitizedFile:original_filename)

CarrierWave::SanitizedFile有一个original_filename包含上传文件的文件名的私有方法。（文档：http://rdoc.info/github/jnicklas/carrierwave/master/CarrierWave/SanitizedFile: original_filename）

After reading through this thread from the CarrierWave mailing list, none seemed to fit my needs. With something like

从 CarrierWave 邮件列表中通读此线程后，似乎没有一个适合我的需求。像这样的东西

class Upload < ActiveRecord::Base
  mount_uploader :file, FileUploader
  # ...

I heavily modify the :filecolumn value from the original filename. Due to this I decided to track the original filename in a separate column from the one bound to CarrierWave. In my FileUploaderI simply added a reader that wraps the private original_filenamemethod:

我:file从原始文件名中大量修改了列值。因此，我决定在与绑定到 CarrierWave 的列不同的列中跟踪原始文件名。在我的FileUploader我只是添加了一个包装私有original_filename方法的阅读器：

def original_file
  original_filename
end

I then added a before_createevent to the Uploadclass (my Uploadrecords are never modified, so a before_createis acceptable for my needs)

然后我before_create向Upload班级添加了一个事件（我的Upload记录从未被修改，所以 abefore_create可以满足我的需要）

before_create do
  self.original_file = self.file.original_file
end

回答by why

This is my solution:

这是我的解决方案：

  before_save :update_file_attributes


  def update_file_attributes
    if file.present? && file_changed? 
      self.content_type = file.file.content_type
      self.file_size = file.file.size
      self.file_name = read_attribute(:file)
    end
  end