Question

如何制作一个下拉菜单，反映数据库中相应列中存储的内容？

我有一个性别选择的下拉菜单，它可以更新数据库但是在刷新的选择菜单中返回默认选项，因为我的所有文本字段都正在提取数据库数据。

<%= form_for @profile, :remote => true,  do |f| %>
Username: <%= @profile.user.username %><br />
URL: http://site.com/<%= @profile.user.username %><br />
First Name: <%= f.text_field :first_name,   %><br />
Last Name: <%= f.text_field :last_name,  %><br />
I am: <%= f.select :gender, options_for_select([['Select Gender', ''],['Male','m'],['Female','f']]) %><br />
<%= f.submit 'update' %><br />
<% end %>

任何线索我错过了什么？亲切的问候

这是我的模特：

class Profile < ActiveRecord::Base

  belongs_to :user

   attr_accessible :first_name, :last_name, :gender, :motd

  # Local Variables
  # Regex Variables
  email_regex = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i
  alpha_regex = /^[a-zA-Z]*$/
  alpha_numeric_regix = /^[a-zA-Z0-9_]*$/


    #Form Validation
    validates :first_name,    :presence      => true,
                              :length        => { :minimum => 2, :maximum => 15 },
                              :format        => {
                                                  :with => alpha_regex,
                                                  :message => "Your first name must contain letters only"
                                                }

    validates :last_name,     :presence      => true,
                              :length        => { :minimum => 2, :maximum => 15 },
                              :format        => {  
                                                  :with => alpha_regex,
                                                  :message => "Your last name must contain letters only"
                                                }

    validates :gender,        :presence      => true,
                              :inclusion     => { 
                                                  :in => %w( m f ), :message => "Are you male or female?"
                                                }


end

从控制器更新方法

 def update

   respond_to do |format|

     if @profile.update_attributes(params[:profile])

       format.js   { render :js => "window.location = '#{settings_edit_profile_path}'" } 
       flash[:success] = "Profile updated" 
     else
      format.js   { render :form_errors }

    end
  end
end

Answer 1

options_for_select具有选择值的特殊语法：

<%= f.select :gender, options_for_select([['Select Gender', ''],['Male','m'],['Female','f']], "#{@profile.gender}") %>

可能会像您期望的那样工作。

或者您可以创建一个Gender模型并使用collection_select默认执行此操作：

<%= f.collection_select :gender, Gender.all, :value, :description, :prompt => true %>

如何让下拉菜单反映存储在ruby on rails中相应数据库列中的内容？

1 个答案: