如何使用DataMapper和Sinatra的复选框进行操作？ [英] How do I work with checkboxes with DataMapper and Sinatra?

问题描述

我想做一个简单的房间管理服务。房间有这些属性：

I'm trying to make a simple room management service. The rooms have these properties:

class Room
  include DataMapper::Resource
  validates_is_unique :number

  property :id, Serial
  property :number, Integer
  property :guest, String
  property :status, Enum[ :free, :occupied ], :default => :free
end

然后我创建一个这样的新房间

Then I create a new room like this

post '/new' do
  content_type :json
  @room = Room.new :guest => params[:guest],
                   :number => params[:number],
                   :status => params[:status]
  if @room.save
    { :number => @room.number, :guest => @room.guest, :status => @room.status }.to_json
  end
end

%form#new_message{:action => '/new', :method => 'post'}
        %p
          %input{:type => "text",      :id => "number", :name => "number"}
          %input{:type => "text",      :id => "guest",  :name => "guest"}
          %input{:type => "checkbox",  :id => "status", :name => "status", :value => "occupied"}
          %input{:type => "submit", :value => "post"}

当选中此框时：状态为已占用取消选中对象将不会保存。我认为它会工作，因为它默认为自由，但没有...

When the box is checked the :status is "occupied" but when I leave it unchecked the object won't save. I thought it would work since it is defaulted to "free" but no...

推荐答案

对于任何愚蠢的原因，如果未点击，则不会提交。这意味着他们不在你的应用程序的哈希。当你说：status => params [：status] 你真的说：status => nil。因为你设置了一个值，它会检查你的枚举，而nil不在你的枚举，所以它失败验证。 （根据你如何使用它，看起来不应该是一个布尔值称为占用或可用？）

For whatever stupid reason, checkboxes do not get submitted if they are not clicked. This means they are not in the hash that hits your app. When you say :status => params[:status] you are really saying :status => nil. Since you have set a value, it checks that against your enum, and nil is not in your enum, so it fails validations. (based on how you are using this, doesn't it seem like it should be a boolean called either "occupied" or "available" ?)

无论如何，你可以显式地将其设置为自由，或者不设置它，并让默认值来处理它。这就是我选择检查时，通过移动到一个质量分配。我使用的代码如下。

Anyway, you could either explicitly set it to free, or not set it at all, and let the default take care of it. That is what I opted for when checking it, by moving it into a mass assignment. The code I used is below.

require 'rubygems'
require 'sinatra'
require 'haml'
require 'dm-core'
require 'dm-validations'
require 'dm-types'
require 'dm-migrations'
require 'sqlite3'


configure do
  class Room
    include DataMapper::Resource
    validates_uniqueness_of :number
    property :id, Serial
    property :number, Integer
    property :guest, String
    property :status, Enum[ :free, :occupied ], :default => :free
  end
  set :sessions , true
  DataMapper::Logger.new($stdout, :debug)
  DataMapper.setup( :default , "sqlite3://#{Dir.pwd}/development.sqlite3" )  
  DataMapper.finalize
  DataMapper.auto_upgrade!
end


get '/' do
  @rooms = Room.all
  haml :index
end

post '/new' do
  p params
  @room = Room.new params[:room]
  if @room.save
    session[:flash] = "room reserved"
    redirect '/'
  else
    session[:flash] = @room.errors.to_a
    redirect '/new'
  end
end

get '/new' do
  haml :new
end

__END__
@@layout
!!!
%html
  #flash
    = session[:flash].inspect
  = yield

@@new
%form#new_message{:action => '/new', :method => 'post' , :name => 'room' }
  %p
    %input{:type => "text",      :id => "number", :name => "room[number]"}
    %input{:type => "text",      :id => "guest",  :name => "room[guest]"}
    %input{:type => "checkbox",  :id => "status", :name => "room[status]", :value => "occupied"}
    %input{:type => "submit", :value => "post"}

@@index
%table
  - @rooms.each do |room|
    %tr
      %td= room.number
      %td= room.guest
      %td= room.status

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