使用微信接口，无论是自动登录还是微信支付我们首先需要获取的就是openid,获取openid的方式有两种，一种是在关注的时候进行获取，这种订阅号就可以获取的到，第二种是通过网页授权获取，这种获取需要的是认证服务号。

今天我要说的是第二种网页授权获取openid。下面是我写的一个关于获取openid的类

<?php

/**

 * 微信授权相关接口

 * 

 * @link http://www.phpddt.com

 */

class Wchat

{

   private $app_id = 'wx444444444444';

   private $app_secret = '77777777';

   private $state='aaaa';

  /**

   * 获取微信授权链接

   * 

   * @param string $redirect_uri 跳转地址

   * @param mixed $state 参数

   */

  public function get_authorize_url($redirect_uri = '', $state = '')

  {

    $redirect_uri = urlencode($redirect_uri);

    return "https://open.weixin.qq.com/connect/oauth2/authorize?appid={$this->app_id}&redirect_uri={$redirect_uri}&response_type=code&scope=snsapi_userinfo&state={$state}#wechat_redirect";

  }

   /**

   * 获取微信openid

   */

  public function getOpenid($turl)

  {

    if (!isset($_GET['code'])){

      //触发微信返回code码

       

       $url=$this->get_authorize_url($turl, $this->state);

       

      Header("Location: $url");

      exit();

    } else {

      //获取code码，以获取openid

      $code = $_GET['code'];

      $access_info = $this->get_access_token($code);

      return $access_info;

    }

     

  }

  /**

   * 获取授权token网页授权

   * 

   * @param string $code 通过get_authorize_url获取到的code

   */

  public function get_access_token($code = '')

  {

   $appid=$this->app_id;

   $appsecret=$this->app_secret;

    

    $token_url = "https://api.weixin.qq.com/sns/oauth2/access_token?app&secret=".$appsecret."&code=".$code."&grant_type=authorization_code";

    //echo $token_url;

    $token_data = $this->http($token_url);

    // var_dump( $token_data);

    if($token_data[0] == 200)

    {

      $ar=json_decode($token_data[1], TRUE);

      return $ar;

    }

     

    return $token_data[1];

  }

   

   

  public function http($url, $method='', $postfields = null, $headers = array(), $debug = false)

  {

    $ci = curl_init();

    /* Curl settings */

    curl_setopt($ci, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);

    curl_setopt($ci, CURLOPT_CONNECTTIMEOUT, 30);

    curl_setopt($ci, CURLOPT_TIMEOUT, 30);

    curl_setopt($ci, CURLOPT_RETURNTRANSFER, true);

 

    switch ($method) {

      case 'POST':

        curl_setopt($ci, CURLOPT_POST, true);

        if (!empty($postfields)) {

          curl_setopt($ci, CURLOPT_POSTFIELDS, $postfields);

          $this->postdata = $postfields;

        }

        break;

    }

    curl_setopt($ci, CURLOPT_URL, $url);

    curl_setopt($ci, CURLOPT_HTTPHEADER, $headers);

    curl_setopt($ci, CURLINFO_HEADER_OUT, true);

 

    $response = curl_exec($ci);

    $http_code = curl_getinfo($ci, CURLINFO_HTTP_CODE);

 

    if ($debug) {

      echo "=====post data======\r\n";

      var_dump($postfields);

 

      echo '=====info=====' . "\r\n";

      print_r(curl_getinfo($ci));

 

      echo '=====$response=====' . "\r\n";

      print_r($response);

    }

    curl_close($ci);

    return array($http_code, $response);

  }

 

}

?>