各种demo——CI框架学习

寒假学习一下CI框架，请各位多多指教！

一.CI的HelloWorld！

注意：CI禁止直接通过文件目录来访问控制器。

 ./application/controllers/hello.php
 1 <?php
//放止用户直接通过路径来访问控制器，如果这样的话会显示找不到（封装）
if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Hello extends CI_Controller {

    public function sayhello($name,$name2){
        echo $name,",Hello CI to ",$name2;
    }
}

 

二.CI的文本计时器demo——文本操作与调用视图操作

调用视图的基本格式：

$this->load->view('XXX');

<?php
//./applications/controllers/hello.php
//放止用户直接通过路径来访问控制器，如果这样的话会显示找不到（封装）
if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Hello extends CI_Controller {

    public function sayhello($name,$name2){
        echo $name,",Hello CI to ",$name2;
    }

    public function show(){
        $name = "deng";
        @$count = file_get_contents('./num.txt');  //装饰器
        $count = $count ? $count:0;
        $count++;
        $data = array('key'=>$name,'value'=>$count);

        $re = fopen('./num.txt','w');
        fwrite($re, $count);

        $this->load->view("testview.php",$data);   //装载两个视图页面
        $this->load->view("testview2.php");
    }
}

三.CI的数据库demo——对数据模型的增，删，改，查

数据模型——

1.数据模型是一个数据库类

2.一个模型针对一张表

创建一个模型必须注意——

必须继承数据核心类CI_Model，同时重载父类中的构造方法

class Model_name extends CI_Model
{
    function __construct()
    {
        parent::__construct();
    }
}

对数据库的操作——

1.连接数据库（$this->load->database());

2.插入数据（$this->db->insert($t_name,$arr);)

$t_name——你要操作的表]

$arr——你要插入的数据("key"=>value)

3.更新数据

$this->db->where(字段名，字段值)

$this->db->update(表名，修改值的数组)

4.查询数据

$this->db->where(字段名，字段值)

$this->db->select(字段)

$query = $this->db->get(表名)

return $query->result();

5.删除数据

$this->db->where(字段名，字段值)

$this->db->delete(表名)

./application/controllers/user.php
<?php 
if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class User extends CI_Controller {

    public function insert(){
        $this->load->model('test_m');
        $arr = array('usid'=>1,'uname'=>'deng1','upass'=>'1234');
        $this->test_m->user_insert($arr);
    }

    public function update(){
        $this->load->model('test_m');
        $arr = array('usid'=>22,'uname'=>'deng222','upass'=>'1233333');
        $this->test_m->user_update(2,$arr);
    }

    public function delete(){
        $this->load->model('test_m');
        $this->test_m->user_delete(22);
    }

    public function select()
    {
        $this->load->model('test_m');
        $arr = $this->test_m->user_select(1);
        print_r($arr);
        echo $arr[0]->usid;

    }
}

/* End of file welcome.php */
/* Location: ./application/controllers/welcome.php */

<?php
/**
*  ./application/models/test_m.php
*/
class Test_m extends CI_Model
{
    
    function __construct()
    {
        parent::__construct();
        //connect to the database
        $this->load->database();
        //$this->load->insert($t_name,$data)
    }

    function user_insert($arr){
        $this->db->insert('user',$arr);
    }

    function user_update($id,$arr)
    {
        $this->db->where('usid',$id);
        $this->db->update('user',$arr);
    }

    function user_delete($id){
        $this->db->where('usid',$id);
        $this->db->delete('user');
    }

    function user_select($id){
        $this->db->where('usid',$id);
        $this->db->select('*');
        $query = $this->db->get('user');
        return  $query->result();
    }
}
?>

 四.CI的文件上传demo

 1.面向过程的文件上传方法

#/controllers/upload.php
<?php 
if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Upload extends CI_Controller {

    //显示带表单的视图
    public function index(){
        $this->load->view('up');

    }

    //显示上传信息
    public function up(){

        if(!empty($_POST['sub'])){
            //打印变量的函数
            //var_dump($_FILES['upfile']);   
            $file = $_FILES['upfile'];
            if($file['size'] >= 20000000){
                echo "size no!";
            }
            else{
                switch ($file['type']) {
                    case 'image/jpeg':
                        $br = '.jpg';
                        break;
                    
                    default:
                        $br = false;
                        break;
                }

                if($br){
                    $time = time();
                    move_uploaded_file($file['tmp_name'], "./upload/$time$br");

                }
                else{
                    echo "type no";
                }
            }

        }
    }

}

#/views/up.php
<html>
<!--注意相对路径的建立-->
    <form action="/CI/index.php/upload/up" method="post" enctype="multipart/form-data">
        <input type="file" name="upfile" />
        <input type="submit" name="sub" value="提交" />
    
    </form>
</html>

 2.面向对象的CI框架文件上传方法

 a.定义一个数组，设置一些与上传相关的参数

//设置上传目录，这里写./,目录要建在网站根目录，就是和application同级

//如果你要放在application目录下，可以用系统定义的路径常量APPPATH

//例如：APPPATH.'uploads/'

$config['upload_path'] = './uploads/';

//设置允许上传的类型

$config['allowed_types'] = 'gif|jpg|png';

$config['max_size'] = '100';

//如果是图片还可以设置最大高度和宽度

$config['max_height'] = 768;

$config['max_width'] = 1024;

b.还可以设置其他的一些额外参数，详细看用户手册

c.调用CI的上传通用类，并执行上传

//upload为调用的类名，全小写

$this->load->library('upload',$config);

//如果上传框的name写的是userfile，那就不用传参数了，如果不是，把name的值传进去

$this->upload->do_upload('上传框的name');

d.接收出错信息或成功信息

//出错信息

$error = array('error' => $this->upload->display_error());

//成功信息

$data = array('upload_data' => $this->upload->data());

<?php 
if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Upload extends CI_Controller {

    //显示带表单的视图
    public function index(){
        $this->load->view('up');

    }

    //显示上传信息
    public function up(){

        $config['upload_path'] = './uploads/';
        $config['allowed_types'] = 'gif|jpg|png';
        $config['max_size'] = "2000";

        $this->load->library('upload',$config);

        //打印成功或错误的信息
        if($this->upload->do_upload('upfile'))
        {
            $data = array("upload_data" => $this->upload->data());
            var_dump($data);
        }
        else
        {
            $error = array("error" => $this->upload->display_errors());
            var_dump($error);
        }
    }

}

 五.CI的登录验证demo

1.利用CI类实现session登录

a.修改配置文件（config.php）

$config['encryption_key']

b.加载SESSION类

$this->load->library('session');

c.创建SESSION

$this->session->set_userdata($array);

d.查看SESSION

$this->session->userdata(session名);

e.删除SESSION

$this->session->unset_userdata('SESSION名');

./application/controllers/login.php
<?php 
if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Login extends CI_Controller {

    public function index()
    {
        $this->load->view('login.html');
    }

    public function checklogin(){
        $this->load->model("test_m");
        $user = $this->test_m->user_select($_POST['uname']);
        if($user){
            if($user[0]->upass == $_POST['upass']){
                echo '密码正确！';
                $this->load->library('session');
                $arr = array("uid" => $user[0]->usid);
                $this->session->set_userdata($arr);
                echo "<br />";
                echo $this->session->userdata('uid');
            }
            else{
                echo '密码不正确！';
            }
        }
        else{
            echo '用户名不存在';
        }
    }

    public function checksession(){
        $this->load->library('session');
        if($this->session->userdata('uid')){
            echo '已经登录。';
        }
        else{
            echo '没有登录。';
        }
    }

    public function loginout(){
        $this->load->library('session');
        $this->session->unset_userdata('uid');
    }
}

 六.CI的分页功能demo

1.必须知道的一些参数

a.总共有多少条记录

b.一页要有多少条记录

c.总共多少页

d.当前页前后要显示多少个分页链接

2.设置一些CI分页类基本参数

//总条数

$config['total_rows']

//一页显示几条

$config['per_page']

//定义当前页的前后各有几个数字链接

$config['num_links']

//定义没有分页参数,主URL

$config['base_url']

3.调用CI的分页类

$this->load->library('pagination');

4.执行分页方法

$this->pagination->initialize($config);

5.输出分页链接

echo $this->pagination->create_links();

6.查询部分数据(limit)

echo $this->db->limit($num,$start);  //从$start查$num条

./applications/controllers/page.php
<?php 
if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Page extends CI_Controller {

    public function user_add(){
        $this->load->model('test_m');

        for ($i = 1;$i <= 100;$i++){
            $name = 'u'.$i;
            $arr = array("usid"=>$i,"uname"=>$name,"upass"=>123456);
            $this->test_m->user_insert($arr);

        }
    }

    public function pagelist(){
        $this->load->model('test_m');
        $user = $this->test_m->user_select_all();
        $allnum = count($user);
        $pagenum = 20;

        $config['total_rows'] = $allnum;
        $config['per_page'] = $pagenum;
        $config['num_links'] = 3;
        $config['base_url'] = "/CI/index.php/page/pagelist";
        $config['use_page_numbers'] = true;

        $this->load->library('pagination');
        $this->pagination->initialize($config);

        var_dump($this->pagination->create_links());
        echo $this->pagination->create_links();

        echo "<br />";
        $id = $this->uri->segment(3);  //获得url第三段字符
        $id =$id ? $id:1;
        $start = ($id - 1) * $pagenum;
        $list = $this->test_m->user_select_limit($start,$pagenum);
        var_dump($list);
    }
}