我有钱币宝石的问题。我试图显示所有货币的下拉列表：
观点：
<% if @receipt.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(@receipt.errors.count, "error") %> prohibited this receipt from being saved:</h2>
<ul>
<% @receipt.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<%= simple_form_for(@receipt, :html => {:class => 'form-horizontal', :multipart => true }) do |f| %>
<h3>Kassenzettel hinzufügen</h3>
<p>
<div class="input-prepend">
<%= f.label :due_date, 'Ausstellungsdatum' -%>
<span class="add-on"><i class="icon-calendar"></i></span><%= f.text_field :due_date, :value => Date.today.strftime('%d.%m.%Y'), :class => 'datepicker span2', :"data-date-format" => :'dd.mm.yyyy' %>
</p>
<p>
<%= f.label :due_time, 'Zeit (optional)' -%>
<%= f.time_select :due_time, { :class => "adsf"} %>
</p>
<p>
<%= f.select(:currency,all_currencies(Money::Currency::TABLE), {:include_blank => 'Select a Currency'}) %>
</p>
<p> <%= f.label :recipt, 'Datei hochladen' -%> <%= f.file_field :document -%>
<p class="help-block">Akzeptierte Formate: PDF, JPG, TIFF, max. 1 MB</p>
</p>
<br />
<p>
<button type="submit" class="btn btn-success"><i class="icon-plus icon-white"></i> Dokument hinzufügen </button>
<%= link_to 'Abbrechen', receipts_path, :class => "btn" %></p>
<% end %>
模特：
class Receipt < ActiveRecord::Base
belongs_to :user
has_many :products, :dependent => :destroy
self.per_page = 5
validates :due_date, :presence => true
validates_attachment :document, :presence => true,
:size => { :in => 0..5024.kilobytes }
has_attached_file :document,
:styles => {
:minithumb=> ["50x50#", :png],
:thumb=> ["150x150#", :png],
:small => ["500>", :png] },
:convert_options => { :all => '-background white -flatten +matte'}
attr_accessible :due_date, :due_time, :receiptissuedate, :document, :dependent => :destroy
columns_hash["due_time"] = ActiveRecord::ConnectionAdapters::Column.new("due_time", nil, "time")
composed_of :receiptfinalamount,
:class_name => "Money",
:mapping => [%w(receiptfinalamount cents), %w(receiptcurrency currency_as_string)],
:constructor => Proc.new { |cents, currency| Money.new(cents || 0, currency || Money.default_currency) },
:converter => Proc.new { |value| value.respond_to?(:to_money) ? value.to_money : raise(ArgumentError, "Can't convert #{value.class} to Money") }
before_validation(:on => :create) do
self.receiptissuedate = DateTime.new(self.due_date.year, self.due_date.month, self.due_date.day, self.due_time.hour, self.due_time.min)
end
before_save :default_values
def default_values
self.receiptfinalamount ||= 0
end
def due_date
return @due_date if @due_date.present?
return Date.today
end
def due_time
return @due_time if @due_time.present?
return Time.now
end
def due_date=(new_date)
@due_date = self.string_to_datetime(new_date, I18n.t('date.formats.default'))
end
def due_time=(new_time)
@due_time = self.string_to_datetime(new_time, I18n.t('time.formats.time'))
end
protected
def string_to_datetime(value, format)
return value unless value.is_a?(String)
begin
DateTime.strptime(value, format)
rescue ArgumentError
nil
end
end
end
控制器：
class ReceiptsController < ApplicationController
helper_method :sort_column, :sort_direction
# GET /receipts
# GET /receipts.json
def index
#@receipts = Receipt.all
@receipts = current_user.receipts.order(sort_column + " " + sort_direction).paginate(:page => params[:page]).order('receiptissuedate DESC')
respond_to do |format|
format.html # index.html.erb
format.json { render json: @receipts }
end
end
# GET /receipts/1
# GET /receipts/1.json
def show
@receipt = current_user.receipts.find(params[:id])
@products = current_user.receipts.find(params[:id]).products.all
@product = Product.new
respond_to do |format|
format.html # show.html.erb
format.json { render json: @receipt }
end
end
# GET /receipts/new
# GET /receipts/new.json
def new
@receipt = Receipt.new
respond_to do |format|
format.html # new.html.erb
format.json { render json: @receipt }
end
end
# GET /receipts/1/edit
def edit
@receipt = Receipt.find(params[:id])
end
# POST /receipts
# POST /receipts.json
def create
@receipt = current_user.receipts.new(params[:receipt])
respond_to do |format|
if @receipt.save
format.html { redirect_to receipts_url, notice: 'Receipt was successfully created.' }
format.json { render json: @receipt, status: :created, location: @receipt }
else
format.html { render action: "new" }
format.json { render json: @receipt.errors, status: :unprocessable_entity }
end
end
end
# PUT /receipts/1
# PUT /receipts/1.json
def update
@receipt = current_user.receipts.find(params[:id])
respond_to do |format|
if @receipt.update_attributes(params[:receipt])
format.html { redirect_to @receipt, notice: 'Receipt was successfully updated.' }
format.json { head :no_content }
else
format.html { render action: "edit" }
format.json { render json: @receipt.errors, status: :unprocessable_entity }
end
end
end
# DELETE /receipts/1
# DELETE /receipts/1.json
def destroy
@receipt = current_user.receipts.find(params[:id])
@receipt.destroy
respond_to do |format|
format.html { redirect_to receipts_url }
format.json { head :no_content }
end
end
private
def sort_column
Receipt.column_names.include?(params[:sort]) ? params[:sort] : "receiptissuedate"
end
def sort_direction
%w[asc desc].include?(params[:direction]) ? params[:direction] : "desc"
end
end
错误：
收据中的NameError＃new
显示/Users/dastrika/Documents/RailsProjects/receipter/app/views/receipts/_form_new.html.erb第22行：
未初始化的常数Money :: Currency :: TABLE
提取的来源（第22行）：
19：＆lt;％= f.label：due_time，＆＃39; Zeit（可选）＆＃39; - ％GT;
20：
21：＆lt;％= f.time_select：due_time，{：class =＆gt; ＆＃34; adsf＆＃34;}％＆gt;
22：
24：＆lt;％= f.select（：currency，all_currencies（Money :: Currency :: TABLE），{：include_blank =＆gt;＆＃39;选择货币＆＃39;}）％＆gt; 25：
模板包含跟踪：app / views / receipts / new.html.erb
Rails.root：/ Users / dastrika / Documents / RailsProjects / receipter 应用程序跟踪|框架跟踪|完整跟踪
app / views / receipts / _form_new.html.erb:22:in block in _app_views_receipts__form_new_html_erb__159753442_6920660'
app/views/receipts/_form_new.html.erb:11:in _ app_views_receipts__form_new_html_erb__159753442_6920660＆＃39;
app / views / receipts / new.html.erb:7:in _app_views_receipts_new_html_erb__164008852_34408570'
app/controllers/receipts_controller.rb:38:in new＆＃39;
答案 0 :(得分：2)
此语法不正确
Money::Currency::TABLE
你想要
all_currencies(Money::Currency.table)
def all_currencies(hash)
hash.keys
end
答案 1 :(得分：0)
运行example from the rubymoney docs时出现类似的错误消息
Money.new(1000, "USD") == Money.new(1000, Currency.new("USD"))
NameError: uninitialized constant Currency
要解决此问题，我只需在Money::的调用之前加上Currency，就像这样：
Money.new(1000, "EUR").currency == Money::Currency.new("EUR")
=> true