前言：本节将以Codeigniter 4.0.3为基础，讲解一个注册和登陆的案例
0.安装Wamp环境（略）
wamp使用得比较普遍，我使用的是PHP 7.3 的版本。安装步骤网上很多，略过。
1.安装配置CI4
下载ci4的源代码报，解压到wamp的www/ci4signup/文件夹中
拷贝app/public/的.htaccess和index.php到app/下，以此来去掉路径中的public。
修改app/index.php,去掉…/， 代码如下
$pathsPath = realpath(FCPATH . 'app/Config/Paths.php');
浏览器输入http://localhost/ci4signup/，结果如下：
修改app/Config/App.php
public $baseURL = 'http://localhost/ci4signup/';
public $indexPage = '';
小试身手，做个测试：
app/controllers/Home.php
<?php namespace App\Controllers;
class Home extends BaseController
{
public function index()
{
return view('welcome_message');
}
public function method(){
echo '没错，就是我';
}
}
http://localhost/ci4signup/home/method， 结果如下
配置数据库
建立个数据库ci4signup， 修改配置
app/Config/database.php
<?php namespace Config;
/**
* Database Configuration
*
* @package Config
*/
class Database extends \CodeIgniter\Database\Config
{
/**
* The directory that holds the Migrations
* and Seeds directories.
*
* @var string
*/
public $filesPath = APPPATH . 'Database/';
/**
* Lets you choose which connection group to
* use if no other is specified.
*
* @var string
*/
public $defaultGroup = 'default';
/**
* The default database connection.
*
* @var array
*/
public $default = [
'DSN' => '',
'hostname' => 'localhost',
'username' => 'root',
'password' => '',
'database' => 'ci4signup',
'DBDriver' => 'MySQLi',
'DBPrefix' => '',
'pConnect' => false,
'DBDebug' => (ENVIRONMENT !== 'production'),
'cacheOn' => false,
'cacheDir' => '',
'charset' => 'utf8',
'DBCollat' => 'utf8_general_ci',
'swapPre' => '',
'encrypt' => false,
'compress' => false,
'strictOn' => false,
'failover' => [],
'port' => 3306,
];
/**
* This database connection is used when
* running PHPUnit database tests.
*
* @var array
*/
public $tests = [
'DSN' => '',
'hostname' => '127.0.0.1',
'username' => '',
'password' => '',
'database' => ':memory:',
'DBDriver' => 'SQLite3',
'DBPrefix' => 'db_', // Needed to ensure we're working correctly with prefixes live. DO NOT REMOVE FOR CI DEVS
'pConnect' => false,
'DBDebug' => (ENVIRONMENT !== 'production'),
'cacheOn' => false,
'cacheDir' => '',
'charset' => 'utf8',
'DBCollat' => 'utf8_general_ci',
'swapPre' => '',
'encrypt' => false,
'compress' => false,
'strictOn' => false,
'failover' => [],
'port' => 3306,
];
//--------------------------------------------------------------------
public function __construct()
{
parent::__construct();
// Ensure that we always set the database group to 'tests' if
// we are currently running an automated test suite, so that
// we don't overwrite live data on accident.
if (ENVIRONMENT === 'testing')
{
$this->defaultGroup = 'tests';
// Under Travis-CI, we can set an ENV var named 'DB_GROUP'
// so that we can test against multiple databases.
if ($group = getenv('DB'))
{
if (is_file(TESTPATH . 'travis/Database.php'))
{
require TESTPATH . 'travis/Database.php';
if (! empty($dbconfig) && array_key_exists($group, $dbconfig))
{
$this->tests = $dbconfig[$group];
}
}
}
}
}
}
2.session的角色
session是CI框架中至关重要的传递数据的媒介，这里小试身手做个演示，看看里面的内容是什么：
<?php namespace App\Controllers;
class Home extends BaseController
{
public function index()
{
return view('welcome_message');
}
public function method(){
}
public function setsession(){
$mysession = session();
var_dump($mysession);
echo '==============';
$myarray = [
'name'=>'yyys',
'email'=>'yyyfadfs',
'add'=>'yyysfadga'
];
$mysession->set('key',$myarray);
}
public function getsession(){
$mysession = session();
var_dump($mysession->get('key'));
}
public function destroysession(){
$mysession = session();
$mysession->destroy();
}
}
以此输入http://localhost/ci4signup/home/setsession， 和
http://localhost/ci4signup/home/getsession， http://localhost/ci4signup/home/destroysession， http://localhost/ci4signup/home/getsession查看结果。
3.创建User控制器
app/controllers/User.php
注意，这里对路由进行配置如下
app/Config/Routes.php
/**
* --------------------------------------------------------------------
* Router Setup
* --------------------------------------------------------------------
*/
$routes->setDefaultNamespace('App\Controllers');
$routes->setDefaultController('user');
$routes->setDefaultMethod('index');
$routes->setTranslateURIDashes(false);
$routes->set404Override();
$routes->setAutoRoute(true);
$routes->get('/', 'user::index');
app/Controllers/User.php
<?php namespace App\Controllers;
class User extends BaseController{
public function index(){
echo 'I am fine';
}
public function register(){
// echo '注册开始';
helper('form');
return view('signup');
}
public function newuser(){
$myvalues = $this->validate([
'name'=>'required',
'email'=>'required',
'password'=>'required',
]);
if(!$myvalues){
//没有通过条件检验
return $this->register();
}else{
//通过条件检验后，取值
$myrequest = \Config\Services::request();
echo $myrequest->getVar('name');
echo $myrequest->getVar('email');
echo $myrequest->getVar('password');
}
}
}
app/Views/signup.php
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Register a New User</title>
</head>
<body>
<?php
echo \Config\Services::validation()->listErrors();
echo form_open('user/newuser');
echo 'Enter your name ', form_input('name','',''), '<br>';
echo 'Enter your password ', form_input('password','',''), '<br>';
echo 'Enter your email ', form_input('email','',''), '<br>';
echo form_submit('','Create Now');
echo form_close();
?>
</body>
</html>
http://localhost/ci4signup/user/register进行测试
至此，实现了一个简单的form条件验证以及取值。
后面的讲解从model开始。