我们在Rails中使用ActiveRecord的"序列化"功能,如下所示:
class User < ActiveRecord::Base
serialize :favorite_colors, Array
....
end
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所以我们可以拥有
u = User.last
u.favorite_colors = [ 'blue', 'red', 'grey' ]
u.save!
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因此,基本上ActiveRecord将上面的数组序列化并将其存储在一个名为favorite_colors的数据库字段中.
我的问题是:如何让用户在表单中输入他喜欢的颜色?你使用一系列文本字段吗?一旦他们进入,你如何在表格中显示他们编辑?
这是与序列化数组属性的Rails表单助手相关的问题.
谢谢
这里已经存在类似的问题Rails + CarrierWave:NoMethodError:nil的未定义方法`name':NilClass但解决方案是修复错字.
我已经在同一个项目中使用Rails和Carrierwave,没有任何问题.有一个简单的AR模型:
class Upload < ActiveRecord::Base
attr_accessible :title, :data_file, :caption
mount_uploader :upload, DataFileUploader
validates :title, :data_file, :presence => true
end
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在控制器中,它们像往常一样:
def create
@upload = Upload.new(params[:upload])
if @upload.save
redirect_to new_admin_upload_path, :notice => t("site.successfully_created_resource")
else
render :action => 'new'
end
end
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直接前进.提交表单时发生以下错误:
ActiveRecord::StatementInvalid in Admin::UploadsController#create
NoMethodError: undefined method `name' for nil:NilClass: INSERT INTO "uploads" ("caption",
"created_at", "data_file", "title", "updated_at") VALUES (?, ?, ?, ?, ?)
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我没有看到错误并且不明白,名称来自何处.当离开mount_uploader:upload,在AR模型中的DataFileUploader时,一切正常.
这有什么不对?
非常感谢!
问题是如何对具有以下结构的数组进行排序:
\n\nstatus = \n [["Wartend", :pending],\n ["Schufa Check", :schufa_check],\n ["Schufa Key existiert", :schufa_person_key_exists],\n ["LottoIdent", :lotto_ident],\n ["IBAN existiert", :iban_exists],\n ["E-Mail Best\xc3\xa4tigung", :email_validation],\n ["SMS Best\xc3\xa4tigung", :mobile_validation],\n ["Aktiv", :active],\n ["gesperrt", :locked],\n ["ausgeschlossen", :locked_out],\n ["werden gel\xc3\xb6scht", :marked_for_deletion]]\nRun Code Online (Sandbox Code Playgroud)\n\n结果应该是这样的:
\n\n[["Aktiv", :active], \n ["ausgeschlossen", :locked_out], \n ["E-Mail Best\xc3\xa4tigung", :email_validation], \n ["gesperrt", :locked], \n ["IBAN existiert", :iban_exists], \n ["LottoIdent", :lotto_ident], \n ["Schufa Check", :schufa_check], \n ["Schufa Key existiert", :schufa_person_key_exists], \n ["SMS Best\xc3\xa4tigung", :mobile_validation], \n ["Wartend", :pending], \n ["werden gel\xc3\xb6scht", :marked_for_deletion]]\nRun Code Online (Sandbox Code Playgroud)\n