读 Agile Web Development with Rails Second Edition 读书笔记 (三)

1.类级的变量 及 form.select 中 prompt 的作用 及 validates_inclusion_of 的用法
p 137

ruby 代码

form.select :pay_type, Order::PAYMENT_TYPES, :prompt => "select a payment method"

class Order < ActiveRecord::Base
  validates_inclusion_of :pay_type, :in => PAYMENT_TYPES.map { | disp, value| value}
  PAYMENT_TYPES = [
    # Displayed   stored in db
    ["Check", "check"],
    ["credit card", "cc"],
    ["purchase order "]
  ]

prompt  空的选择的提示


2.保存未登录用户访问的 uri 在他登录后自动转向
p 159

ruby 代码

session[:original_uri] = request.request_uri
uri = session[:original_uri]
session[:original_uri] = nil
redirect_to(uri || {:action => "index" })

3.link_to 可以加 method => "post"

4.删除的事务 这样做后可以自动回滚
def after_destroy
  if User.count.zero?
    raise "Can't delete last user."
  end
end

5. logger.info(" ..info .. ")

6.use curl test REST
> curl -H "Accept: application/xml" http://localhost:3000/info/who_bought/1
> curl -H "Accept: text/html" http://localhost:3000/info/who_bought/1

7.render :xml => @product.to_xml(:include => :orders)

xml 代码

<product>
  <name>new_product<!---->name>
  <orders>
    <order>
      <id>100<!---->id>
      <price>200<!---->price>
    <order>
    <order>
      <id>101<!---->id>
      <price>202<!---->price>
    <order>
  <!---->orders>
<!---->product>

<product><orders><order><id>
    </id>

8.
# HTML 模式文档
rake doc:app
# code stats
rake stats 
</order></orders>

</product>