Question

我对Rails很新。我想要做的是访问销售的分支名称和产品名称。我指定了三个模型（销售，分公司，产品）的协会。但是，我无法检索值。在“index.html.erb”视图中，它显示分支名称和产品名称的nil值。如何访问这些值？

sale.rb

class Sale < ActiveRecord::Base
  belongs_to :branch, :class_name => "Branch", :foreign_key => :branch_code
  belongs_to :product, :class_name => "Product", :foreign_key => :product_sku
end

branch.rb

class Branch < ActiveRecord::Base
    has_many :sales, :class_name => "Sale", :foreign_key => :branch_code
end

product.rb

class Product < ActiveRecord::Base
    has_many :sales, :class_name => "Sale", :foreign_key => :product_sku
end

index.html.erb

<h1>Sales Index</h1>

<h2>Files in database</h2>
<table border=2>
    <tr>
        <th>Branch Name</th>
        <th>Product Name</th>
        <th>Qty. Sold</th>
        <th>End of day Qty</th>
        <th>Date</th>
        <th>Date Created</th>
        <th>Date Last Modified</th>
    </tr>

    <% @sales.each do |sale| %>
        <tr>
            <td><%= sale.branch %></td>
            <td><%= sale.product %></td>
            <td><%= sale.quantity_sold %></td>
            <td><%= sale.end_of_day_quantity %></td>
            <td><%= sale.salesdate %></td>
            <td><%= sale.created_at %></td>
            <td><%= sale.updated_at %></td>
        </tr>
    <% end %>
</table>

sales_controller.rb

class SalesController < ApplicationController
    def index
        @files = Dir.glob('/Users/xxyy/Documents/rails/Dummy/*.csv')
        #@mapper = Array.new() 
        require 'csv'
        require 'fileUtils'
        for file in @files

            filename = File.basename(file, ".*")
            date = filename[22..31]
            csv_text = File.read(file)

            CSV.foreach(file, :headers => true) do |row|
                Sale.create(:branch_code => row[0], :product_sku => row[1], :quantity_sold => row[2], :end_of_day_quantity => row[3], :salesdate => date)
            end
            FileUtils.mv(file, '/Users/xxyy/Documents/rails/Read/')
        end
        @sales = Sale.all

    end
end

schema.rb

ActiveRecord::Schema.define(version: 20140812013013) do

  create_table "branches", force: true do |t|
    t.string   "branch_code"
    t.string   "branch_name"
    t.datetime "created_at"
    t.datetime "updated_at"
  end

  create_table "products", force: true do |t|
    t.string   "product_sku"
    t.string   "product_name"
    t.datetime "created_at"
    t.datetime "updated_at"
  end

  create_table "sales", force: true do |t|
    t.string   "branch_code"
    t.string   "product_sku"
    t.integer  "quantity_sold"
    t.integer  "end_of_day_quantity"
    t.integer  "branch_id"
    t.integer  "product_id"
    t.datetime "created_at"
    t.datetime "updated_at"
    t.datetime "salesdate"
  end

  add_index "sales", ["branch_id"], name: "index_sales_on_branch_id"
  add_index "sales", ["product_id"], name: "index_sales_on_product_id"

end

Answer 1

确保您已正确完成关联。

class Product < ActiveRecord::Base
  has_many :sales, :class_name => "Sale", :foreign_key => :product_sku
end

Answer 2

has_many :sales

这需要是复数。

class Branch < ActiveRecord::Base
    has_many :sales
end

你不需要在这里指定类名，外键应该是branch_id（我猜测），也不需要指定。

无法访问其他模型的值

2 个答案: