小编Sye*_*Ali的帖子

以下是ActionMailer指南的简短片段

    class UserMailer < ActionMailer::Base
  default :from => "notifications@example.com"

  def welcome_email(user)
    @user = user
    @url  = "http://example.com/login"
    mail(:to => user.email,
         :subject => "Welcome to My Awesome Site")
  end

end

并在控制器中

class UsersController < ApplicationController
  # POST /users
  # POST /users.xml
  def create
    @user = User.new(params[:user])

    respond_to do |format|
      if @user.save
        # Tell the UserMailer to send a welcome Email after save
        UserMailer.welcome_email(@user).deliver

        format.html { redirect_to(@user, :notice => 'User was successfully created.') }
        format.xml  { render :xml => @user, :status => …

我有两个型号,

User 
Membership

两者之间有以下关系

user has_many :memberships

我一直试图找出构建方法所在的位置,以及如何在实例的方法列表中获取它.这是显示我的delima的调试器的输出

(rdb:63) @user.memberships.respond_to?"build"
true

虽然以下是返回false,但它不会返回true？

(rdb:63) @user.memberships.instance_methods.include?"build"
false