使用CodeIgniter开发用户登录注册模块

本文介绍使用CodeIgniter来开发一个用户登录和注册的小模块，有详细的数据库表和ci代码。

1、数据库设计

2、文件列表

控制器：Account.php

模型：Maccount.php

视图：
account/dashboard.php
account/details.php
account/login.php
account/logout.php
account/note.php
account/register.php

3、登录

a) 控制器

 /**
      * 接收、验证登录表单
      * 表单规则在配置文件:/config/form_validation.php
         'account/login'=>array(                        //登录表单的规则
             array(
                 'field'=>'username',
                 'label'=>'用户名',
                 'rules'=>'trim|required|xss_clean|callback_username_check'
             ),
             array(
                 'field'=>'password',
                 'label'=>'密码',
                 'rules'=>'trim|required|xss_clean|callback_password_check'
             )
         )
      * 错误提示信息在文件：/system/language/english/form_validation.php
      */
     function login()
     {
         //设置错误定界符
         $this->form_validation->set_error_delimiters('<span class="error">', '</span>');
 
         $this->_username = $this->input->post('username');                //用户名
         if ($this->form_validation->run() == FALSE)
         {
             $this->load->view('account/login');
         }
         else
         {
             //注册session,设定登录状态
             $this->MAccount->login($this->_username);
             $data['message'] = $this->session->userdata('username').' You are logged in! Now take a look at the '
                                 .anchor('account/dashboard', 'Dashboard');
             $this->load->view('account/note', $data);
         }
         }
 
 //登录表单验证时自定义的函数
 /**
      * 提示用户名是不存在的登录
      * @param string $username
      * @return bool
      */
     function username_check($username)
     {
         if ($this->MAccount->get_by_username($username))
         {
             return TRUE;
         }
         else
         {
             $this->form_validation->set_message('username_check', '用户名不存在');
             return FALSE;
         }
     }
     /**
      * 检查用户的密码正确性
      */
     function password_check($password)
     {
         $password = md5($this->salt.$password);
         if ($this->MAccount->password_check($this->_username, $password))
         {
             return TRUE;
         }
         else
         {
             $this->form_validation->set_message('password_check', '用户名或密码不正确');
             return FALSE;
         }
     }

b) 模型

 /**
      * 添加用户session数据,设置用户在线状态
      * @param string $username
      */
     function login($username)
     {
         $data = array('username'=>$username, 'logged_in'=>TRUE);
         $this->session->set_userdata($data);                    //添加session数据
         }
     /**
      * 通过用户名获得用户记录
      * @param string $username
      */
     function get_by_username($username)
     {
         $this->db->where('username', $username);
         $query = $this->db->get('user');
         //return $query->row();                            //不判断获得什么直接返回
         if ($query->num_rows() == 1)
         {
             return $query->row();
         }
         else
         {
             return FALSE;
         }
     }
    
     /**
      * 用户名不存在时,返回false
      * 用户名存在时，验证密码是否正确
      */
     function password_check($username, $password)
     {               
         if($user = $this->get_by_username($username))
         {
             return $user->password == $password ? TRUE : FALSE;
         }
         return FALSE;                                    //当用户名不存在时
     }

c) 视图

4、注册

与表单登录的操作是相似的

a)控制器

 /**
      * 用户注册
      * 表单规则在配置文件:/config/form_validation.php
         'account/register'=>array(                    //用户注册表单的规则
             array(
                 'field'=>'username',
                 'label'=>'用户名',
                 'rules'=>'trim|required|xss_clean|callback_username_exists'
             ),
             array(
                 'field'=>'password',
                 'label'=>'密码',
                 'rules'=>'trim|required|min_length[4]|max_length[12]
 |matches[password_conf]|xss_clean'
             ),
             array(
                 'field'=>'email',
                 'label'=>'邮箱账号',
                 'rules'=>'trim|required|xss_clean|valid_email|callback_email_exists'
             )
         )
      * 错误提示信息在文件：/system/language/english/form_validation.php
      */
     function register()
     {
         //设置错误定界符
         $this->form_validation->set_error_delimiters('<span class="error">', '</span>');
        
         if ($this->form_validation->run() == FALSE)
         {
             $this->load->view('account/register');
         }
         else
         {
             $username = $this->input->post('username');
             $password = md5($this->salt.$this->input->post('password'));
             $email = $this->input->post('email');
             if ($this->MAccount->add_user($username, $password, $email))
             {
                 $data['message'] = "The user account has now been created! You can go "
                             .anchor('account/index', 'here').'.';
             }
             else
             {
                 $data['message'] = "There was a problem when adding your account. You can register "
                             .anchor('account/register', 'here').' again.';
             }
             $this->load->view('account/note', $data);
         }       
         }
 /**
      * ======================================
      * 用于注册表单验证的函数
      * 1、username_exists()
      * 2、email_exists()
      * ======================================
      */
     /**
      * 验证用户名是否被占用。
      * 存在返回false, 否者返回true.
      * @param string $username
      * @return boolean
      */
     function username_exists($username)
     {
         if ($this->MAccount->get_by_username($username))
         {
             $this->form_validation->set_message('username_exists', '用户名已被占用');
             return FALSE;
         }
         return TRUE;
     }
     function email_exists($email)
     {
         if ($this->MAccount->email_exists($email))
         {
             $this->form_validation->set_message('email_exists', '邮箱已被占用');
             return FALSE;
         }
         return TRUE;
     }

b)模型

     /**
      * 添加用户
      */
     function add_user($username, $password, $email)
     {
         $data = array('username'=>$username, 'password'=>$password, 'email'=>$email);
         $this->db->insert('user', $data);
         if ($this->db->affected_rows() > 0)
         {
             $this->login($username);
             return TRUE;
         }
         return FALSE;
         }
 /**
      * 检查邮箱账号是否存在.
      * @param string $email
      * @return boolean
      */
     function email_exists($email)
     {
         $this->db->where('email', $email);
         $query = $this->db->get('user');
         return $query->num_rows() ? TRUE : FALSE;
     }

5、退出

 /**
      * 用户退出
      * 已经登录则退出，否者转到details
      */
     function logout()
     {
         if ($this->MAccount->logout() == TRUE)
         {
             $this->load->view('account/logout');
         }
         else
         {
             $this->load->view('account/details');
         }
         }

模型：

/**
      * 注销用户
      * @return boolean
      */
     function logout()
     {
         if ($this->logged_in() === TRUE)
         {
             $this->session->sess_destroy();                //销毁所有session的数据
             return TRUE;
         }
         return FALSE;
     }

6、  遗留问题

a) 没有使用验证码

b) 表单规则验证时，怎样使当上一个表单某项（如：姓名）出现问题时，停止对后面表单项的验证（如密码等）。比如在登录时，提示用户名不存在，就没必要验证是否填写了密码或者密码有错误