Why do I get the error: TypeError in UsersController#create can't convert String into Hash

Question

我正在尝试实现电子邮件功能，以便当有人注册时他们会收到一封电子邮件。我正在遵循本指南：http://guides.rubyonrails.org/action_mailer_basics.html

但我收到错误消息：

TypeError in UsersController#create
can't convert String into Hash

application_mailer.rb:

class ApplicationMailer < ActionMailer::Base
  default "from@example.com"
  layout 'mailer'
end

user_mailer.rb:

class UserMailer < ApplicationMailer
  default from: 'notifications@example.com'

  def welcome_email(user)
    @user = user
    @url  = 'http://localhost:3000/users/login'
    mail(to: @user.email, subject: 'Welcome to My Awesome Site')
  end
end

views/user_mailer/welcome_email.html.erb:

<!DOCTYPE html>
<html>
  <head>
    <meta content='text/html; charset=UTF-8' http-equiv='Content-Type' />
  </head>
    <body>
    <h1>Welcome to example.com, <%= @user.name %></h1>
    <p>
      You have successfully signed up to example.com,
      your username is: <%= @user.login %>.<br>
    </p>
    <p>
      To login to the site, just follow this link: <%= @url %>.
    </p>
    <p>Thanks for joining and have a great day!</p>
  </body>
</html>

views/user_mailer/welcome_email.txt.erb

Welcome to example.com, <%= @user.name %>
===============================================

You have successfully signed up to example.com,
your username is: <%= @user.login %>.

To login to the site, just follow this link: <%= @url %>.

Thanks for joining and have a great day!

以及users_controller中的创建方法：

def create
  @user = User.new(user_params)
if @user.save
  # login is achieved by saving a user's 'id' in a session variable, 
  # accessible to all pages
   UserMailer.welcome_email(@user).deliver_later
  session[:user_id] = @user.id
  redirect_to films_path
else
  render action: "new"
end
end

User_params 在 user_controller:

def user_params 
    params.require(:user).permit(:password, :password_confirmation, :role, :first_name, :last_name, :house_no, :street, :town, :postcode, :email, :date_of_birth) 
end

完整错误：

TypeError in UsersController#create
can't convert String into Hash
Extracted source (around line #0):           

Rails.root: C:/Sites/Thor/Under Construction/ThorCinema/new/Lab/ThorCinema
Application Trace | Framework Trace | Full Trace

app/mailers/application_mailer.rb:2:in `<class:ApplicationMailer>'
app/mailers/application_mailer.rb:1:in `<top (required)>'
app/mailers/user_mailer.rb:1:in `<top (required)>'
app/controllers/users_controller.rb:33:in `create'

有人可以帮忙吗。

Answer 1

default 引用 ActionMailer

中的散列

所以这一行是不正确的，因为它指定的是字符串而不是散列

default "from@example.com"

应该是

default sender: "from@example.com"

参见

中的"Default Hash"部分

http://api.rubyonrails.org/classes/ActionMailer/Base.html

编辑

请注意，您的完整轨迹甚至为您指出了直线...

app/mailers/application_mailer.rb:2:在`'

Why do I get the error: TypeError in UsersController#create can't convert String into Hash

Why do I get the error: TypeError in UsersController#create can't convert String into Hash

ruby

email

methods

ruby-on-rails

ruby-on-rails-3