【ror学习笔记7】表单

一。创建模型

1.创建模型及数据表

depot>ruby script/generate model order

depot>ruby script/generate model line_item

2.修改数据表，添加表间关系

修改迁移006_create_orders.rb

class CreateOrders < ActiveRecord::Migration
  def self.up
    create_table :orders do |t|
      t.column :name, :string
      t.column :address, :text
      t.column :email , :string
      t.column :pay_type, :string, :limit => 10
    end
  end

  def self.down
    drop_table :orders
  end
end

修改迁移007_create_line_items.rb

class CreateLineItems < ActiveRecord::Migration
  def self.up
    create_table :line_items do |t|
      t.column :product_id, :integer, :null =>false
      t.column :order_id, :integer, :null =>false
      t.column :quantity, :integer, :null =>false
      t.column :total_price, :decimal, :null =>false, 
                   :precision =>8, :scale =>2
      end
      execute "alter table line_items add constraint 
      fk_line_item_products foreign key(product_id) 
      references products(id) "
      execute "alter table line_items add constraint 
      fk_line_item_orders foreign key(order_id) 
      references orders(id) "
  end

  def self.down
    drop_table :line_items
  end
end

depot>rake dg:migrate

3.修改模型添加模型间关系

class Order < ActiveRecord::Base
      has_many :line_items

end

 

class Product < ActiveRecord::Base
      has_many :line_items
end

 

class LineItem < ActiveRecord::Base
      belongs_to :order
      belongs_to :product

end

 

 

 

 

二。创建表单搜集订单信息

1.在视图添加按钮

app\views\store\_cart.rhtml

<div class="cart-title">Your Cart </div>
<table>
   <%= render(:partial =>"cart_item" , :collection => cart.items)  %>
   <tr class="total-line">
        <td colspan = "2">Total</td>
    <td class="total-cell"><%=number_to_currency(@cart.total_price) %></td>
   </tr>
   
</table>

<%=button_to "Checkout", :action=>:checkout %>
<%= button_to "Empty cart" , :action=>:empty_cart%>

2.在控制器添加方法

store_controller.rb

    def checkout
      @cart = find_cart
      if @cart.items.empty?
        redirect_to_index("Your cart is empty")
          else
          @order = Order.new
          end
    end

3.添加方法的视图

views/store/checkout.rhtml

<div class="depot-form">
<%= error_messages_for 'order' %>
<fieldset>
      <legend>Please Enter Your Details </legend>
      
      <% form_for :order, :url=>{:action => :save_order} do |form| %>
        <p>
          <label for="order_name">Name:</label>
          <%= form.text_field :name, :size => 40 %>
        </p>
        
        <p>
          <label for="order_address">Address:</label>
          <%= form.text_area :address, :rows => 3, :cols => 40 %>
        </p>
        
        <p>
          <label for="order_email">E-mail:</label>
          <%= form.text_field :email, :size => 40 %>
        </p>
        
        <p>
          <label for="order_pay_type">Pay with:</label>
          <%=
            form.select :pay_type,
                      Order::PAYMENT_TYPES,
                      :prompt => "Select a payment method "
          %>
        </p>
        
        <%= submit_tag "Place Order", :class => "submit" %>
      <% end %>
</fieldset>
</div>

4.在模型中添加数据选择项目和数据校验

class Order < ActiveRecord::Base
      has_many :line_items
      PAYMENT_TYPES = [
        #Displayed    stored in db
        ["Check",    "check"],
        ["Credit card" ,     "cc"],
        ["purchase order",    "po"]
      ]
      validates_presence_of :name, :address, :email, :pay_type
      validates_inclusion_of :pay_type, :in =>PAYMENT_TYPES.map{|disp,value|value}
      

end

 

三。搜集表单信息存储到数据库

1.在视图添加按钮（已添加）

2.在控制器添加方法

store_controller.rb

    def save_order
      @cart = find_cart
      @order = Order.new(params[:order])
      @order.add_line_items_from_cart(@cart)
      if @order.save
        session[:cart] = nil
        redirect_to_index("Thank you for your order")
        else
          render :action=>:checkout
        end
      end

3.在模型中添加相关方法

class Order < ActiveRecord::Base
      has_many :line_items
      PAYMENT_TYPES = [
        #Displayed    stored in db
        ["Check",    "check"],
        ["Credit card" ,     "cc"],
        ["purchase order",    "po"]
      ]
      validates_presence_of :name, :address, :email, :pay_type
      validates_inclusion_of :pay_type, :in =>PAYMENT_TYPES.map{|disp,value|value}
      
      def add_line_items_from_cart (cart)
        cart.items.each do |item|
          li = LineItem.from_cart_item(item)
          line_items  << li
        end
      end

end

 

class LineItem < ActiveRecord::Base
      belongs_to :order
      belongs_to :product
      
      def self.from_cart_item(cart_item)
        li = self.new
        li.product = cart_item.product
        li.quantity = cart_item.quantity
        li.total_price = cart_item.price
        li
      end
end