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 2 //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） 3 if ( ! defined(‘BASEPATH‘)) exit(‘No direct script access allowed‘); 4 5 class Hello extends CI_Controller { 6 7 public function sayhello($name,$name2){ 8 echo $name,",Hello CI to ",$name2; 9 } 10 }
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：
$this->load->view(‘XXX‘);
1 <?php
2 //./applications/controllers/hello.php
3 //放止用户直接通过路径来访问控制器，如果这样的话会显示找不到（封装）
4 if ( ! defined(‘BASEPATH‘)) exit(‘No direct script access allowed‘);
5
6 class Hello extends CI_Controller {
7
8 public function sayhello($name,$name2){
9 echo $name,",Hello CI to ",$name2;
10 }
11
12 public function show(){
13 $name = "deng";
14 @$count = file_get_contents(‘./num.txt‘); //装饰器
15 $count = $count ? $count:0;
16 $count++;
17 $data = array(‘key‘=>$name,‘value‘=>$count);
18
19 $re = fopen(‘./num.txt‘,‘w‘);
20 fwrite($re, $count);
21
22 $this->load->view("testview.php",$data); //装载两个视图页面
23 $this->load->view("testview2.php");
24 }
25 }
三.CI的数据库demo——对数据模型的增，删，改，查
数据模型——
1.数据模型是一个数据库类
2.一个模型针对一张表
创建一个模型必须注意——
必须继承数据核心类CI_Model，同时重载父类中的构造方法
class Model_name extends CI_Model
{
function __construct()
{
parent::__construct();
}
}
对数据库的操作——
1.连接数据库（$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)
1 ./application/controllers/user.php
2 <?php
3 if ( ! defined(‘BASEPATH‘)) exit(‘No direct script access allowed‘);
4
5 class User extends CI_Controller {
6
7 public function insert(){
8 $this->load->model(‘test_m‘);
9 $arr = array(‘usid‘=>1,‘uname‘=>‘deng1‘,‘upass‘=>‘1234‘);
10 $this->test_m->user_insert($arr);
11 }
12
13 public function update(){
14 $this->load->model(‘test_m‘);
15 $arr = array(‘usid‘=>22,‘uname‘=>‘deng222‘,‘upass‘=>‘1233333‘);
16 $this->test_m->user_update(2,$arr);
17 }
18
19 public function delete(){
20 $this->load->model(‘test_m‘);
21 $this->test_m->user_delete(22);
22 }
23
24 public function select()
25 {
26 $this->load->model(‘test_m‘);
27 $arr = $this->test_m->user_select(1);
28 print_r($arr);
29 echo $arr[0]->usid;
30
31 }
32 }
33
34 /* End of file welcome.php */
35 /* Location: ./application/controllers/welcome.php */
1 <?php
2 /**
3 * ./application/models/test_m.php
4 */
5 class Test_m extends CI_Model
6 {
7
8 function __construct()
9 {
10 parent::__construct();
11 //connect to the database
12 $this->load->database();
13 //$this->load->insert($t_name,$data)
14 }
15
16 function user_insert($arr){
17 $this->db->insert(‘user‘,$arr);
18 }
19
20 function user_update($id,$arr)
21 {
22 $this->db->where(‘usid‘,$id);
23 $this->db->update(‘user‘,$arr);
24 }
25
26 function user_delete($id){
27 $this->db->where(‘usid‘,$id);
28 $this->db->delete(‘user‘);
29 }
30
31 function user_select($id){
32 $this->db->where(‘usid‘,$id);
33 $this->db->select(‘*‘);
34 $query = $this->db->get(‘user‘);
35 return $query->result();
36 }
37 }
38 ?>
四.CI的文件上传demo
1.面向过程的文件上传方法
1 #/controllers/upload.php
2 <?php
3 if ( ! defined(‘BASEPATH‘)) exit(‘No direct script access allowed‘);
4
5 class Upload extends CI_Controller {
6
7 //显示带表单的视图
8 public function index(){
9 $this->load->view(‘up‘);
10
11 }
12
13 //显示上传信息
14 public function up(){
15
16 if(!empty($_POST[‘sub‘])){
17 //打印变量的函数
18 //var_dump($_FILES[‘upfile‘]);
19 $file = $_FILES[‘upfile‘];
20 if($file[‘size‘] >= 20000000){
21 echo "size no!";
22 }
23 else{
24 switch ($file[‘type‘]) {
25 case ‘image/jpeg‘:
26 $br = ‘.jpg‘;
27 break;
28
29 default:
30 $br = false;
31 break;
32 }
33
34 if($br){
35 $time = time();
36 move_uploaded_file($file[‘tmp_name‘], "./upload/$time$br");
37
38 }
39 else{
40 echo "type no";
41 }
42 }
43
44 }
45 }
46
47 }
1 #/views/up.php 2 <html> 3 <!--注意相对路径的建立--> 4 <form action="/CI/index.php/upload/up" method="post" enctype="multipart/form-data"> 5 <input type="file" name="upfile" /> 6 <input type="submit" name="sub" value="提交" /> 7 8 </form> 9 </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());
1 <?php
2 if ( ! defined(‘BASEPATH‘)) exit(‘No direct script access allowed‘);
3
4 class Upload extends CI_Controller {
5
6 //显示带表单的视图
7 public function index(){
8 $this->load->view(‘up‘);
9
10 }
11
12 //显示上传信息
13 public function up(){
14
15 $config[‘upload_path‘] = ‘./uploads/‘;
16 $config[‘allowed_types‘] = ‘gif|jpg|png‘;
17 $config[‘max_size‘] = "2000";
18
19 $this->load->library(‘upload‘,$config);
20
21 //打印成功或错误的信息
22 if($this->upload->do_upload(‘upfile‘))
23 {
24 $data = array("upload_data" => $this->upload->data());
25 var_dump($data);
26 }
27 else
28 {
29 $error = array("error" => $this->upload->display_errors());
30 var_dump($error);
31 }
32 }
33
34 }
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‘);
1 ./application/controllers/login.php
2 <?php
3 if ( ! defined(‘BASEPATH‘)) exit(‘No direct script access allowed‘);
4
5 class Login extends CI_Controller {
6
7 public function index()
8 {
9 $this->load->view(‘login.html‘);
10 }
11
12 public function checklogin(){
13 $this->load->model("test_m");
14 $user = $this->test_m->user_select($_POST[‘uname‘]);
15 if($user){
16 if($user[0]->upass == $_POST[‘upass‘]){
17 echo ‘密码正确！‘;
18 $this->load->library(‘session‘);
19 $arr = array("uid" => $user[0]->usid);
20 $this->session->set_userdata($arr);
21 echo "<br />";
22 echo $this->session->userdata(‘uid‘);
23 }
24 else{
25 echo ‘密码不正确！‘;
26 }
27 }
28 else{
29 echo ‘用户名不存在‘;
30 }
31 }
32
33 public function checksession(){
34 $this->load->library(‘session‘);
35 if($this->session->userdata(‘uid‘)){
36 echo ‘已经登录。‘;
37 }
38 else{
39 echo ‘没有登录。‘;
40 }
41 }
42
43 public function loginout(){
44 $this->load->library(‘session‘);
45 $this->session->unset_userdata(‘uid‘);
46 }
47 }
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
1 ./applications/controllers/page.php
2 <?php
3 if ( ! defined(‘BASEPATH‘)) exit(‘No direct script access allowed‘);
4
5 class Page extends CI_Controller {
6
7 public function user_add(){
8 $this->load->model(‘test_m‘);
9
10 for ($i = 1;$i <= 100;$i++){
11 $name = ‘u‘.$i;
12 $arr = array("usid"=>$i,"uname"=>$name,"upass"=>123456);
13 $this->test_m->user_insert($arr);
14
15 }
16 }
17
18 public function pagelist(){
19 $this->load->model(‘test_m‘);
20 $user = $this->test_m->user_select_all();
21 $allnum = count($user);
22 $pagenum = 20;
23
24 $config[‘total_rows‘] = $allnum;
25 $config[‘per_page‘] = $pagenum;
26 $config[‘num_links‘] = 3;
27 $config[‘base_url‘] = "/CI/index.php/page/pagelist";
28 $config[‘use_page_numbers‘] = true;
29
30 $this->load->library(‘pagination‘);
31 $this->pagination->initialize($config);
32
33 var_dump($this->pagination->create_links());
34 echo $this->pagination->create_links();
35
36 echo "<br />";
37 $id = $this->uri->segment(3); //获得url第三段字符
38 $id =$id ? $id:1;
39 $start = ($id - 1) * $pagenum;
40 $list = $this->test_m->user_select_limit($start,$pagenum);
41 var_dump($list);
42 }
43 }
原文：http://www.cnblogs.com/lovezbs/p/4548068.html