我正在做饭订餐系统，我是Rails的新手，我想知道如何在DB中保存记录（从餐馆订购的餐点）作为文本。例如，我在 db / seed.rb 中有一份餐馆和餐点列表，当我在订单中查看餐馆的餐点时查看订购的餐点（餐点名称和名称）餐厅）我看到餐厅的id和用餐的id。我知道这很容易解决，但我不知道去做这件事。
let data = {
name: 'Somebody',
address: {
city: 'somewhere'
},
tags: [{
id: 5
name: 'new'
}]
}
check(data, 'where') // should be true
db/seed.rb
Restaurant.create(name: "PizzaHut")
Restaurant.create(name: "Salad Story")
Restaurant.create(name: "KFC")
Meal.create(name: "PizzaHut Special - 32cm", restaurant_id: Restaurant.find_by(name: "PizzaHut").id)
Meal.create(name: "PizzaHut Special - 42cm", restaurant_id: Restaurant.find_by(name: "PizzaHut").id)
Meal.create(name: "Pepperoni - 32cm", restaurant_id: Restaurant.find_by(name: "PizzaHut").id)
Meal.create(name: "Pepperoni - 42cm", restaurant_id: Restaurant.find_by(name: "PizzaHut").id)
Meal.create(name: "Hawaii - 32cm", restaurant_id: Restaurant.find_by(name: "PizzaHut").id)
Meal.create(name: "Hawaii - 42cm", restaurant_id: Restaurant.find_by(name: "PizzaHut").id)
Meal.create(name: "Diablo - 32cm", restaurant_id: Restaurant.find_by(name: "PizzaHut").id)
Meal.create(name: "Diablo - 42cm", restaurant_id: Restaurant.find_by(name: "PizzaHut").id)
Meal.create(name: "Longer + Small Drink (Coca-Cola, Fanta, Sprite)", restaurant_id: Restaurant.find_by(name: "KFC").id)
Meal.create(name: "Longer + Large Drink (Coca-Cola, Fanta, Sprite)", restaurant_id: Restaurant.find_by(name: "KFC").id)
Meal.create(name: "Greek Salad - Medium", restaurant_id: Restaurant.find_by(name: "Salad Story").id)
Meal.create(name: "Greek Salad - Large", restaurant_id: Restaurant.find_by(name: "Salad Story").id)
Meal.create(name: "Salad Story Special - Medium", restaurant_id: Restaurant.find_by(name: "Salad Story").id)
Meal.create(name: "Salad Story Special - Large", restaurant_id: Restaurant.find_by(name: "Salad Story").id)
staticpages/home.html.erb <h1 class="jumbotron-font">Order your meal</h1>
<div class="row">
<div class="col-md-6 col-md-offset-3">
<%= form_for(:orders, url: new_order_path) do |f| %>
<%= f.label :restaurant, "Restaurant" %>
<%= f.collection_select :restaurant_id, Restaurant.order(:name), :id,
:name, {prompt: "Select a restaurant"}, {class: "form-control"} %>
<%= f.label :meal, "Choose your meal" %>
<%= f.grouped_collection_select :meal_id, Restaurant.order(:name),
:meals, :name, :id, :name, {prompt: "Select a meal"},
{class: "form-control"} %>
<%= f.label :suggestions, "Suggestions" %>
<%= f.text_area :suggestions, rows: "4", placeholder: "e.g. I'd like to change sweetcorn for olives..." %>
<%= f.submit "Place your order", class: "btn btn-primary" %>
<% end %>
</div>
</div>
db/schema.rb我的日志：
ActiveRecord::Schema.define(version: 20161220125950) do
create_table "meals", force: :cascade do |t|
t.string "name"
t.integer "restaurant_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.index ["restaurant_id"], name: "index_meals_on_restaurant_id"
end
create_table "orders", force: :cascade do |t|
t.string "restaurant"
t.string "meal"
t.text "suggestions"
t.integer "user_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.string "restaurant_id"
t.string "meal_id"
t.index ["user_id", "created_at"], name: "index_orders_on_user_id_and_created_at"
t.index ["user_id"], name: "index_orders_on_user_id"
end
create_table "restaurants", force: :cascade do |t|
t.string "name"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "users", force: :cascade do |t|
t.string "provider"
t.string "uid"
t.string "name"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
end
*更新*
Parameters: {"utf8"=>"✓", "authenticity_token"=>"TVdB/YJ8W2fQD0XslA7KwlY2WHPPTSsI6Tx18CE1v6vF9zJLjM5nFd6lO/gSrPwsy/fCnra54TeAtxrwGyIGoQ==", "orders"=>{"restaurant_id"=>"1", "meal_id"=>"11", "suggestions"=>""}, "commit"=>"Place your order"}
User Load (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIMIT ? [["id", 1], ["LIMIT", 1]]
(0.1ms) begin transaction
CACHE (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIMIT ? [["id", 1], ["LIMIT", 1]]
Restaurant Load (0.1ms) SELECT "restaurants".* FROM "restaurants" WHERE "restaurants"."id" = ? LIMIT ? [["id", 1], ["LIMIT", 1]]
SQL (91.1ms) INSERT INTO "orders" ("suggestions", "user_id", "created_at", "updated_at", "restaurant_id", "meal_id") VALUES (?, ?, ?, ?, ?, ?) [["suggestions", ""], ["user_id", 1], ["created_at", 2016-12-20 14:05:13 UTC], ["updated_at", 2016-12-20 14:05:13 UTC], ["restaurant_id", "1"], ["meal_id", "11"]]
(241.2ms) commit transaction
从视图中我只有 class Order < ApplicationRecord
belongs_to :user
belongs_to :restaurant
end
class User < ApplicationRecord
has_many :orders
has_many :restaurants, through: :orders
end
class Meal < ApplicationRecord
belongs_to :restaurant
end
class Restaurant < ApplicationRecord
has_many :orders
has_many :meals
has_many :users, through: :orders
end
order/index.html.erb这是一个简单的应用程序，只是为了练习，所以我想做单页应用程序，而不是实际确认餐厅的订单。我希望能够下订单，然后在历史列表中查看所有订单。
答案 0 :(得分：0)
我通常对选择字段使用f.association。 如果问题出在您的表单中，请在选择字段（主页）上尝试：
class BMap extends PropertyMap<B, BDto> {
@Override
protected void configure() {
using(new BToBDto()).map(source).setC(null);
//Other mappings...
}
}
那或使用.pluck方法说你特意要显示名字：
<%= f.label :restaurant, "Restaurant" %>
<%= f.association :restaurants, collection: Restaurant.order(:name), {prompt: "Select a restaurant"}, {class: "form-control"} %>
<%= f.label :meal, "Choose your meal" %>
<%= f.association :meals, collection: Restaurant.order(:name).meals, {prompt: "Select a meal"},
{class: "form-control"} %>