Question

使用ruby on rails正确上传文件。现在我需要验证我的上传。单击上载后未选择文件时，应验证并显示错误消息。请帮我提供此错误验证的代码。

我的查看文件是（uploadfile.html.erb）：

     <h1>File Upload</h1>
     <%= form_tag({action: :uploadFile}, multipart: true) do %>
     <p><label for="upload_file">Select File</label>
     <%= error_messages_for :data_file %>
     <%= file_field 'upload', 'datafile' %></p>
     <%= submit_tag "Upload" %>
     <%end%>

我的控制器文件是（upload_controller.rb）：

    class UploadController < ApplicationController
    def uploadFile
    post = DataFile.save(params[:upload])
    render :text => "File has been uploaded successfully"
    end
    end

我的模型文件是（data_file.rb）：

    class DataFile < ActiveRecord::Base
    attr_accessor :upload
    validates_attachment_presence :upload unless :upload
    def self.save(upload)
    name =  upload['datafile'].original_filename
    directory = "public/data"
    # create the file path
    path = File.join(directory, name)
    # write the file
    File.open(path, "wb") { |f| f.write(upload['datafile'].read) }
    end
    end

Answer 1

如果您使用的是paperclip gem，则可以在模型中执行此操作。

validates_attachment_presence :datafile unless :datafile

检查上传文件是否存在。

<强>更新

要显示错误消息，只需将此行添加到表单

即可

<%= error_messages_for :upload_file %> #Assuming your model name is `upload_file`

在rails上的ruby中上传文件时出现错误信息

1 个答案: