php 文件中随机取出一条数据四种方法

 <?php
/**
* 文件描述 Session类
* =================================================================
* 文件名称 session.class.php
* -----------------------------------------------------------------
* 适用环境： PHP5.2.x / mysql 5.0.x
* -----------------------------------------------------------------
* 作 者 04ie。com
* -----------------------------------------------------------------
* 创建时间 2010-2-1
* =================================================================
*/
class Session
{
/**
* session默认有效时间
* @access public
* @var ineger $_expiry
*/
public $_expiry = 3600;
/**
* 有效域名
* @access public
* @var string $_domain
*/
public $_domain = '.phpfamily.cn';
//初始化
public function __construct()
{
ini_set('session.use_trans_id', 0);
ini_set('session.gc_maxlifetime', $this->_expiry);
ini_set('session.use_cookie', 1);
ini_set('session.cookie_path', '/');
ini_set('session.cookie_domain', $this->_domain);
session_module_name('user');
session_set_save_handler(
array(&$this, 'open'),
array(&$this, 'close'),
array(&$this, 'read'),
array(&$this, 'write'),
array(&$this, 'destroy'),
array(&$this, 'gc')
);
session_start();
}
/**
* 打开session
* @access public
* @param string $savePath
* @param string $sName
* @return true
*/
public function open($savePath, $sName)
{
$this->_conn = mysql_connect('localhost', 'root', '');
mysql_select_db('databases');
mysql_query('SET NAMES "utf8"');
return true;
}
/**
* 关闭session
* @access public
* @return bool
*/
public function close()
{
return mysql_close($this->_conn);
}
/**
* 读取session
* @access public
* @param string $sid sessionID
* @return mixed
*/
public function read($sid)
{
$sql = "SELECT data FROM sessions WHERE sessionid='%s'";
$sql = sprintf($sql, $sid);
$res = mysql_query($sql, $this->_conn);
$row = mysql_fetch_assoc($res);
return !$row ? null : $row['data'];
}
/**
* 写入session
* @access public
* @param string $sid sessionID
* @param string $data serialize序列化后的session内容
* @return
*/
public function write($sid, $data)
{
$expiry = time() + $this->_expiry;
$sql = "REPLACE INTO sessions (sessionid,expiratio
n,data) VALUES ('%s', '%d', '%s')";
$sql = sprintf($sql, $sid, $expiry, $data);
mysql_query($sql, $this->_conn);
return true;
}
/**
* 销毁session
* @access public
* @param string $sid sessionID
* @return
*/
public function destroy($sid)
{
$sql = "DELETE FROM sessions WHERE sessionid='%s'";
$sql = sprintf($sql, $sid);
mysql_query($sql, $this->_conn);
return true;
}
/**
* 清理过期session
* @access public
* @param integer $time
* @return
*/
public function gc($time = 0)
{
$sql = "DELETE FROM sessions WHERE expiration < '%d'";
$sql = sprintf($sql, time());
mysql_query($sql, $this->_conn);
mysql_query('OPTIMIZE TABLE sessions');
return true;
}
 

<?php
class Cart{
 public function Cart() {
  if(!isset($_SESSION['cart'])){
   $_SESSION['cart'] = array();
  }
 }

 /*
 添加商品
 param int $id 商品主键
    string $name 商品名称
    float $price 商品价格
    int $num 购物数量
 */
 public  function addItem($id,$name,$price,$num,$img) {
  //如果该商品已存在则直接加其数量
  if (isset($_SESSION['cart'][$id])) {
   $this->incNum($id,$num);
   return;
  }
  $item = array();
  $item['id'] = $id;
  $item['name'] = $name;
  $item['price'] = $price;
  $item['num'] = $num;
  $item['img'] = $img;
  $_SESSION['cart'][$id] = $item;
 }

 /*
 修改购物车中的商品数量
 int $id 商品主键
 int $num 某商品修改后的数量，即直接把某商品
 的数量改为$num
 */
 public function modNum($id,$num=1) {
  if (!isset($_SESSION['cart'][$id])) {
   return false;
  }
  $_SESSION['cart'][$id]['num'] = $num;
 }

 /*
 商品数量+1
 */
 public function incNum($id,$num=1) {
  if (isset($_SESSION['cart'][$id])) {
   $_SESSION['cart'][$id]['num'] += $num;
  }
 }

 /*
 商品数量-1
 */
 public function decNum($id,$num=1) {
  if (isset($_SESSION['cart'][$id])) {
   $_SESSION['cart'][$id]['num'] -= $num;
  }

  //如果减少后，数量为0，则把这个商品删掉
  if ($_SESSION['cart'][$id]['num'] <1) {
   $this->delItem($id);
  }
 }

 /*
 删除商品
 */
 public function delItem($id) {
  unset($_SESSION['cart'][$id]);
 }
 
 /*
 获取单个商品
 */
 public function getItem($id) {
  return $_SESSION['cart'][$id];
 }

 /*
 查询购物车中商品的种类
 */
 public function getCnt() {
  return count($_SESSION['cart']);
 }
 
 /*
 查询购物车中商品的个数
 */
 public function getNum(){
  if ($this->getCnt() == 0) {
   //种数为0，个数也为0
   return 0;
  }

  $sum = 0;
  $data = $_SESSION['cart'];
  foreach ($data as $item) {
   $sum += $item['num'];
  }
  return $sum;
 }

 /*
 购物车中商品的总金额
 */
 public function getPrice() {
  //数量为0，价钱为0
  if ($this->getCnt() == 0) {
   return 0;
  }
  $price = 0.00;
  foreach ($this->items as $item) {
   $price += $item['num'] * $item['price'];
  }
  return sprintf("%01.2f", $price);
 }

 /*
 清空购物车
 */
 public function clear() {
  $_SESSION['cart'] = array();
 }
}

<?php

 //获取优酷页面中的flash地址
 function get_flash_url( $url )
 {
  $lines = file($url);
  foreach ($lines as $linenum=> $line) {      
      preg_match_all('|<input type="text" id="link2" value="([^<>]+)" />|',$line,$result);
      $swfurl=$result[1][0];
      if(!empty($swfurl))
    return $swfurl;
  }
 }
?>

<?php

 $url=$_SERVER["QUERY_STRING"];
 
 $flashurl= get_flash_url($url);
 
 echo ( $flashurl );
 
?>

<div class="item"><span class="label">flash地址: </span> <input type="text" id="link2" value="http://player.youku.com/player.php/sid/XMTU1MzcxMzAw/v.swf" />

/tools/web_video.php?url=视频页面地址
eg：/web_video.php?url=http://www.iqiyi.com/dianying/20130217/e72ffd87c2e9c5af.html

<?php 
    session_start(); 
    $k = $_GET['k']; 
    $t = $_GET['t']; 
    //防刷新时间 
    $allowTime = 1800; 
    $ip = get_client_ip(); 
    $allowT = md5($ip . $k . $t); 
    if (!isset($_SESSION[$allowT])) { 
       $refresh = true; 
       $_SESSION[$allowT] = time(); 
    } elseif (time() - $_SESSION[$allowT] > $allowTime) { 
       $refresh = true; 
       $_SESSION[$allowT] = time(); 
    } else { 
       $refresh = false; 
    } 
    ?>  

 <?php   
    /* 改进版
    PHP防止用户刷新页面（Refresh or Reload），重复提交表单内容。
    由于表单变量的内容由$_POST['name']引用，也许在处理完表单后，直接将$_POST['name']销毁（unset()）即可。其实不然。可能由于页面默认对表单内容进行了缓存，所以，即使销毁了$_POST['name']，刷新后，$_POST['name']还是会被赋值，一样有效。  
    可利用Session解决。首先给Session赋个值，比如400，第一次提交成功后改变Session的值，当第二次提交时去检查这个Session 的值，如果不是400，就不再处理表单中的数据。
    可设置Session的有效时间？   
    */ 
    if (isset($_POST['action']) && $_POST['action'] == ’submitted’) {      
         session_start();      
         isset($_SESSION['num']) or die ("no session");      
         if ($_SESSION['num']==400){      
                 print ‘<pre>’;      
                 print_r($_POST);      
                 print ‘<a href="’. $_SERVER['PHP_SELF'] .’">Please try again</a>’;      
                 print ‘</pre>’;      
                 $_SESSION['num']=500;      
         } else {      
                 print ‘<pre>’;      
                 print_r($_POST);      
                 echo "However you have submitted";      
                 print ‘</pre>’;      
         }      
    } else {      
         session_start() or die("session is not started");      
         $_SESSION['num']= 400;       
    ?>     
    <form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="POST">     
    Name: <input type="text" name="personal[name]"><br>     
    Email: <input type="text" name="personal[email]"><br>     
    Beer: <br>     
    <select multiple name="beer[]">     
         <option value="warthog">Warthog</option>     
         <option value="guinness">Guinness</option>     
         <option value="stuttgarter">Stuttgarter Schwabenbr</option>   
    </select><br>     
    <input type="hidden" name="action" value="submitted">     
    <input type="submit" name="submit" value="submit me!">     
    </form>     
    <?php     
    }      
    ?> 

$code = mt_rand(0,1000000);
setcookie('addtips',$code,time()+300);
if(isset($_POST['submit']) ){    
if($_COOKIE['addtips']!= $_POST['code']){            
  echo "请不要刷新本页面或重复提交表单";
exit();
}
}
$smarty->assign('code',$code);

1. <input type="hidden" name="code" value="{$code}"/>

/*利用PHP的Session功能，也能避免PHP表单重复提交。Session保存在服务器端，在PHP运行过程中可以改变Session变量，下次访问这个变量时，得到的是新赋的值，所以，可以用一个Session变量记录表单提交的值，如果不匹配，则认为是用户在重复提交
*/

  session_start();//根据当前SESSION生成随机数  
  $code = mt_rand(0,1000000);  
   $_SESSION['code'] = $code;  
//在表单中隐藏传递：
   < input type="hidden" name="originator" value="< ?=$code?>">

//在接收页代码如下：

 session_start();  
  if(isset($_POST['originator'])) {  
   if($_POST['originator'] ==
   $_SESSION['code']){  
   // 处理该表单的语句，省略  
  }else{  
   echo ‘请不要刷新本页面或
   重复提交表单！’;  
  }  
  }

<?php
//define your token
define("TOKEN", "chenxiang");//改成自己的TOKEN
define('APP_ID', '');//改成自己的APPID
define('APP_SECRET', '');//改成自己的APPSECRET

$wechatObj = new wechatCallbackapiTest(APP_ID,APP_SECRET);
$wechatObj->Run();

class wechatCallbackapiTest
{
    private $fromUsername;
    private $toUsername;
    private $times;
    private $keyword;
    private $app_id;
    private $app_secret;
   
   
    public function __construct($appid,$appsecret)
    {
        # code...
        $this->app_id = $appid;
        $this->app_secret = $appsecret;
    }

    public function valid()
    {
        $echoStr = $_GET["echostr"];
        if($this->checkSignature()){
            echo $echoStr;
            exit;
        }
    }

    /**
     * 运行程序
     * @param string $value [description]
     */
    public function Run()
    {
        $this->responseMsg();
        $arr[]= "您好，这是自动回复，我现在不在，有事请留言，我会尽快回复你的^_^";
        echo $this->make_xml("text",$arr);
    }

    public function responseMsg()
    {  
        $postStr = $GLOBALS["HTTP_RAW_POST_DATA"];//返回回复数据
        if (!empty($postStr)){
                $access_token = $this->get_access_token();//获取access_token
                $this->createmenu($access_token);//创建菜单
                //$this->delmenu($access_token);//删除菜单
                $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
                $this->fromUsername = $postObj->FromUserName;//发送消息方ID
                $this->toUsername = $postObj->ToUserName;//接收消息方ID
                $this->keyword = trim($postObj->Content);//用户发送的消息
                $this->times = time();//发送时间
                $MsgType = $postObj->MsgType;//消息类型
                if($MsgType=='event'){
                    $MsgEvent = $postObj->Event;//获取事件类型
                    if ($MsgEvent=='subscribe') {//订阅事件
                        $arr[] = "你好，我是xxx，现在我们是好友咯![愉快][玫瑰]";
                        echo $this->make_xml("text",$arr);
                        exit;
                    }elseif ($MsgEvent=='CLICK') {//点击事件
                        $EventKey = $postObj->EventKey;//菜单的自定义的key值，可以根据此值判断用户点击了什么内容，从而推送不同信息
                        $arr[] = $EventKey;
                        echo $this->make_xml("text",$arr);
                        exit;
                    }
                }
        }else {
            echo "this a file for weixin API!";
            exit;
        }
    }

    /**
     * 获取access_token
     */

    private function get_access_token()
    {
        $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=".$this->app_id."&secret=".$this->app_secret;
        $data = json_decode(file_get_contents($url),true);
        if($data['access_token']){
            return $data['access_token'];
        }else{

            return "获取access_token错误";
        }
    }

    /**
     * 创建菜单
     * @param $access_token 已获取的ACCESS_TOKEN
     */
    public function createmenu($access_token)
    {
        $url = "https://api.weixin.qq.com/cgi-bin/menu/create?access_token=".$access_token;
        $arr = array(
            'button' =>array(
                array(
                    'name'=>urlencode("生活查询"),
                    'sub_button'=>array(
                        array(
                            'name'=>urlencode("天气查询"),
                            'type'=>'click',
                            'key'=>'VCX_WEATHER'
                        ),
                        array(
                            'name'=>urlencode("身份证查询"),
                            'type'=>'click',
                            'key'=>'VCX_IDENT'
                        )
                    )
                ),
                array(
                    'name'=>urlencode("轻松娱乐"),
                    'sub_button'=>array(
                        array(
                            'name'=>urlencode("刮刮乐"),
                            'type'=>'click',
                            'key'=>'VCX_GUAHAPPY'
                        ),
                        array(
                            'name'=>urlencode("幸运大转盘"),
                            'type'=>'click',
                            'key'=>'VCX_LUCKPAN'
                        )
                    )
                ),
                array(
                    'name'=>urlencode("我的信息"),
                    'sub_button'=>array(
                        array(
                            'name'=>urlencode("关于我"),
                            'type'=>'click',
                            'key'=>'VCX_ABOUTME'
                        ),
                        array(
                            'name'=>urlencode("工作信息"),
                            'type'=>'click',
                            'key'=>'VCX_JOBINFORMATION'
                        )
                    )
                )
            )
        );
        $jsondata = urldecode(json_encode($arr));
        $ch = curl_init();
        curl_setopt($ch,CURLOPT_URL,$url);
        curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
        curl_setopt($ch,CURLOPT_POST,1);
        curl_setopt($ch,CURLOPT_POSTFIELDS,$jsondata);
        curl_exec($ch);
        curl_close($ch);

    }

    /**
     * 查询菜单
     * @param $access_token 已获取的ACCESS_TOKEN
     */
   
    private function getmenu($access_token)
    {
        # code...
        $url = "https://api.weixin.qq.com/cgi-bin/menu/get?access_token=".$access_token;
        $data = file_get_contents($url);
        return $data;
    }

    /**
     * 删除菜单
     * @param $access_token 已获取的ACCESS_TOKEN
     */
   
    private function delmenu($access_token)
    {
        # code...
        $url = "https://api.weixin.qq.com/cgi-bin/menu/delete?access_token=".$access_token;
        $data = json_decode(file_get_contents($url),true);
        if ($data['errcode']==0) {
            # code...
            return true;
        }else{
            return false;
        }

    }
       
    /**
     *@param type: text 文本类型, news 图文类型
     *@param value_arr array(内容),array(ID)
     *@param o_arr array(array(标题,介绍,图片,超链接),...小于10条),array(条数,ID)
     */
   
    private function make_xml($type,$value_arr,$o_arr=array(0)){
        //=================xml header============
        $con="<xml>
                    <ToUserName><![CDATA[{$this->fromUsername}]]></ToUserName>
                    <FromUserName><![CDATA[{$this->toUsername}]]></FromUserName>
                    <CreateTime>{$this->times}</CreateTime>
                    <MsgType><![CDATA[{$type}]]></MsgType>";
                   
          //=================type content============
        switch($type){
         
            case "text" :
                $con.="<Content><![CDATA[{$value_arr[0]}]]></Content>
                    <FuncFlag>{$o_arr}</FuncFlag>"; 
            break;
           
            case "news" :
                $con.="<ArticleCount>{$o_arr[0]}</ArticleCount>
                     <Articles>";
                foreach($value_arr as $id=>$v){
                    if($id>=$o_arr[0]) break; else null; //判断数组数不超过设置数
                    $con.="<item>
                         <Title><![CDATA[{$v[0]}]]></Title>
                         <Description><![CDATA[{$v[1]}]]></Description>
                         <PicUrl><![CDATA[{$v[2]}]]></PicUrl>
                         <Url><![CDATA[{$v[3]}]]></Url>
                         </item>";
                }
                $con.="</Articles>
                     <FuncFlag>{$o_arr[1]}</FuncFlag>"; 
            break;
           
        } //end switch
         
         //=================end return============
        $con.="</xml>";
        
        return $con;
    }

    private function checkSignature()
    {
        $signature = $_GET["signature"];
        $timestamp = $_GET["timestamp"];
        $nonce = $_GET["nonce"];   
               
        $token = TOKEN;
        $tmpArr = array($token, $timestamp, $nonce);
        sort($tmpArr);
        $tmpStr = implode( $tmpArr );
        $tmpStr = sha1( $tmpStr );
       
        if( $tmpStr == $signature ){
            return true;
        }else{
            return false;
        }
    }
}

?>