<?php

 //启用session

 session_start();

 //编码

 header("Content-type: text/html; charset=utf-8");

 //保存微信openid

 $weixin_openid = "";

 //保存从微信得到的code

 $code = "";

 //获得菜单中设置的state值

 $state = "";

 //修改为注册的测试号信息

 $appid = "wx834404c1d1dbb5ec";

 $secret = "bf03cfa823d80dd537bd18e83ce9a4e4";

 if (isset($_GET['code']) && isset($_GET['state']) ){

     $weixin_openid = GetOpenid($_GET['code']);

     $code = $_GET['code'];

     $state = $_GET['state'];

     //echo $resultStr;

 }else{

     echo "NO CODE";

     return ;

 }

 // store session data

 $_SESSION['weixin_openid']=$weixin_openid;

 if($state == "s1"){

     //我的课堂

     header('Location: courseCenter.php');

 }else if($state == "s2"){

     //订单记录

     header('Location: orderList.php');

 }else{

     $textTpl="由认证接口进入我的课堂,<br/>您的 wx_openid: %s <br/> code: %s <br/> state: %s <br/>

     <a href='orderList.php'>订单记录</a>";

     $resultStr = sprintf($textTpl, $weixin_openid, $code, $state);

     echo  $resultStr ;

 }

 //获取微信的openid

 function GetOpenid($c_code)

 {

     $url = "https://api.weixin.qq.com/sns/oauth2/access_token?appid=" . $appid . "&secret=" . $secret . "&code=" . $c_code .  "&grant_type=authorization_code";

     //$url = "http://www.baidu.com";

     $result = getData($url);

     $jsondecode = json_decode($result);

     if($jsondecode != null){

         if(property_exists ( $jsondecode, "openid" ) )

         {

             return $jsondecode->{"openid"};

         }else{

             return "code is invalid.";

         }

     }

     return null;

 }

 //获取https的get请求结果

 function getData($c_url)

 {

     $curl = curl_init(); // 启动一个CURL会话

     curl_setopt($curl, CURLOPT_URL, $c_url); // 要访问的地址

     curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, 0); // 对认证证书来源的检查

     curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, 1); // 从证书中检查SSL加密算法是否存在

     curl_setopt($curl, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']); // 模拟用户使用的浏览器

     curl_setopt($curl, CURLOPT_FOLLOWLOCATION, 1); // 使用自动跳转

     curl_setopt($curl, CURLOPT_AUTOREFERER, 1); // 自动设置Referer

 //    curl_setopt($curl, CURLOPT_POST, 1); // 发送一个常规的Post请求

 //    curl_setopt($curl, CURLOPT_POSTFIELDS, $data); // Post提交的数据包

     curl_setopt($curl, CURLOPT_TIMEOUT, 30); // 设置超时限制防止死循环

     curl_setopt($curl, CURLOPT_HEADER, 0); // 显示返回的Header区域内容

     curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1); // 获取的信息以文件流的形式返回

     $tmpInfo = curl_exec($curl); // 执行操作

     if (curl_errno($curl)) {

        echo 'Errno'.curl_error($curl);//捕抓异常

     }

     curl_close($curl); // 关闭CURL会话

     return $tmpInfo; // 返回数据

 }

 ?>