我已经创建了三个类来表示书籍,人和BookLoans的关联记录之间具有一对多类。虽然我能够通过BookLoans展示人与书的关联,但我一直在播种我的数据库。如何保存在Ruby on Rails的
我现在需要保存一本书的结帐。我打算通过图书管理员来执行此操作。具体而言,在BooksController中创建贷款操作。虽然这在理论上对我来说很有意义,但我有一段可怕的时间来实现适当的语法。
我已经添加了从书籍的展示视图中借阅图书的功能。这个视图现在包含一个表格,它使用账簿管理员的贷款行为来记录贷款。
我已经添加了我认为适合我的Book模型的方法。在theIV的帮助下,我已经在控制器中捕获了适当的信息。不幸的是,当我在书籍展示视图上按下贷款时,book_loan记录没有被记录。
我错过了什么?
Book模型从BooksController中
def loan
@book.add_loan(params[:book_loan][:person_id])
redirect_to :action => 'book', :id => params[:id]
end
书显示视图
class Book < ActiveRecord::Base
has_many :book_loans
has_many :borrowers, :through => :book_loans, :source => :person
accepts_nested_attributes_for :book_loans, :allow_destroy => true
def loaned?
book_loans.exists?(:return_date => nil)
end
def current_borrower
if loaned?
book_loans.first(:order => "out_date desc").person
end
end
def add_loan (person_id)
book_loans.create(:book_id => id,
:person_id => person_id,
:out_date => Date.current)
end
end
贷款方法W /贷款形式
<p>
<b>Title:</b>
<%=h @book.title %>
</p>
<p>
<b>Isbn10:</b>
<%=h @book.isbn10 %>
</p>
<p>
Currently loaned to:
<%=h borrower_name(@book) %>
</p>
<% form_for(@book) do |x| %>
<p>
<%= x.label :loan_person_id %><br/>
<%= collection_select(:book_loan, :person_id,
Person.find(:all, :order => 'name ASC'), :id, :name) %>
<%= x.submit 'Loan', :action => 'loan' %>
</p>
<% end %>
BookLoan型号
class BookLoan < ActiveRecord::Base
belongs_to :book
belongs_to :person
end
角色模型
class Person < ActiveRecord::Base
has_many :book_loans
has_many :books, :through => :book_loans
end
开发日志
Processing BooksController#update (for 127.0.0.1 at 2009-09-24 13:43:05) [PUT]
Parameters: {"commit"=>"Loan", "authenticity_token"=>"XskHLuco7Q7aoEnDfVIiYwVrMEh5uwidvJZdrMbYYWs=", "id"=>"1", "book_loan"=>{"person_id"=>"3"}}
[4;35;1mBook Columns (3.0ms)[0m [0mSHOW FIELDS FROM `books`[0m
[4;36;1mBook Load (4.0ms)[0m [0;1mSELECT * FROM `books` WHERE (`books`.`id` = 1) [0m
[4;35;1mSQL (0.0ms)[0m [0mBEGIN[0m
[4;36;1mBook Load (1.0ms)[0m [0;1mSELECT `books`.id FROM `books` WHERE (`books`.`title` = BINARY 'Dreaming in Code: Two Dozen Programmers, Three Years, 4,732 Bugs, and One Quest for Transcendent Software' AND `books`.id <> 1) LIMIT 1[0m
[4;35;1mSQL (1.0ms)[0m [0mCOMMIT[0m
Redirected to http://localhost:3000/books/1
Completed in 19ms (DB: 10) | 302 Found [http://localhost/books/1]
[4;36;1mSQL (0.0ms)[0m [0;1mSET NAMES 'utf8'[0m
[4;35;1mSQL (0.0ms)[0m [0mSET SQL_AUTO_IS_NULL=0[0m
什么是创建视图的最佳选择。为了简单起见,我想用本书作为跳板点,这就是为什么我想通过person_id。目前我正试图在书籍编辑中添加一个额外的表单。 此外,感谢您的人,我会旋转我的轮子一点。 – ahsteele 2009-09-24 18:35:24
您可以为图书贷款添加一个'fields_for'到您的图书表单。您也可以查看'acceptersted_attributes_for' http://www.railsapi.com/doc/rails-v2.3.4/classes/ActiveRecord/NestedAttributes/ClassMethods.html – theIV 2009-09-24 18:47:42
对不起,扩大一点前面的评论。如果你为你的图书贷款添加一个'fields_for',你应该首先在你的控制器中建立一个图书贷款 - '@ loan = @ book.book_loans.build'-然后在@loan – theIV 2009-09-24 18:49:14