rails 实现登录和注册功能

思路：用户注册需要user这个model, user控制器控制用户的注册功能，session控制器控制用户的登录功能,welcome控制器控制用户登录和退出的跳转,为了表单友好，增加bootstrap样式

生成User model
rails g model user


修改db/migrate生成的文件
class CreateUsers < ActiveRecord::Migration
  def change
    create_table :users do |t|
    t.string :username
    t.string :password
      t.timestamps null: false
    end
  end
end


迁移文件
rake db:migrate

模型验证

class User < ActiveRecord::Base

  validates :username, presence: { message: "用户名不能为空" }
  validates :username, uniqueness: { message: "用户名已存在" }
  validates :password, presence: { message: "密码不能为空" }
  validates :password, length: { minimum: 6, message: "密码长度最短为6位" }

end

生成控制器
rails g controller users
rails g controller sessions
rails g controller welcome


生成对应的路由
resources :users
resources :sessions
root "welcome#index"


生成注册表单

views/users/new.html.erb

用户注册

 

    <%= form_for @user, url: users_path, method: :post do |f| %>
     

       

          <% @user.errors.messages.values.flatten.each do |error| %>
           
• <%= error %>

          <% end -%>
       

     

     

        <%= f.text_field :username, class: "form-control", placeholder: "用户名" %>
     

     

        <%= f.password_field :password, class: "form-control", placeholder: "密码" %>
     

      <%= f.submit "注册", class: "btn btn-primary" %> 
      <%= link_to "登录", new_session_path %>
    <% end -%>
 

 

 

user_controller.rb

class UsersController < ApplicationController

def new
@user = User.new
end

def create
@user = User.new(params.require(:user).permit(:username, :password))
if @user.save
flash[:notice] = '注册成功,请登录'
redirect_to new_session_path
else
render action: :new
end
end

end

生成登录表单

views/sessions/new.html.erb

用户登录

 

    <%= form_tag sessions_path, method: "post" do %>
     

       
     

     

       
     

       
      <%= link_to "注册", new_user_path %>
    <% end %>
 

 

 

sessions_controller.rb


class SessionsController < ApplicationController

def create
@user = User.find_by(username: params[:username], password: params[:password])
if @user
session[:user_id] = @user.id
flash[:notice] = '登录成功'
redirect_to root_path
else
flash[:notice] = "用户名或者密码不正确" 
render action: :new
end
end

def destroy
session[:user_id] = nil
flash[:notice] = "退出成功"
redirect_to root_path
end

end


首页表单

views/welcome/index.html.erb

<% if @user %>
 

欢迎你, <%= @user.username %>

<% else %>
 

Circles 首页

 
<% end -%>

修改layouts/application.html.erb 文件

 
   
   
   
    
    <%= stylesheet_link_tag    'application', media: 'all' %>
    <%= javascript_include_tag 'application' %>
    <%= csrf_meta_tags %>
 
 
   

     

       

         
         

           
             
           
           
              Circles
           
         

         
         

           

             
• 
                  Home
               


              <% if session[:user_id] %>
               
• <%= link_to "#{User.find_by(session[:user_id]).username}, 退出", session_path(session[:user_id]), method: 'delete' %>

              <% else %>
               
• <%= link_to "登录", new_session_path %>

              <% end -%>
           

         

         
       

       
     

   

   

      <% if flash[:notice] %>
       

<%= flash[:notice] %>

      <% end -%>
      
      <%= yield %>