PHP实现微信公众号网页授权

微信网页授权时通过OAuth2.0完成的，整个过程分为三步：

用户授权，获取code；

根据code获取access_token【可通过refresh_token刷新获取较长有效期】

通过access_token和openid获取用户信息

第一种简单封装：

app_id}&redirect_uri={$redirect_uri}&response_type=code&scope=snsapi_userinfo&state={$state}#wechat_redirect";
  }
  
  /**
   * 获取授权token
   * 
   * @param string $code 通过get_authorize_url获取到的code
   */
  public function get_access_token($app_id = '', $app_secret = '', $code = '')
  {
    $token_url = "https://api.weixin.qq.com/sns/oauth2/access_token?appid={$this->app_id}&secret={$this->app_secret}&code={$code}&grant_type=authorization_code";
    $token_data = $this->http($token_url);
    
    if($token_data[0] == 200)
    {
      return json_decode($token_data[1], TRUE);
    }
    
    return FALSE;
  }
  
  /**
   * 获取授权后的微信用户信息
   * 
   * @param string $access_token
   * @param string $open_id
   */
  public function get_user_info($access_token = '', $open_id = '')
  {
    if($access_token && $open_id)
    {
      $info_url = "https://api.weixin.qq.com/sns/userinfo?access_token={$access_token}&openid={$open_id}&lang=zh_CN";
      $info_data = $this->http($info_url);
      
      if($info_data[0] == 200)
      {
        return json_decode($info_data[1], TRUE);
      }
    }
    
    return FALSE;
  }
  
  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);
  }
 
}

第二种先实现两步获取access_token；：

1.用户授权，获取code：

access_token($code);
    	// echo $json;
    }

可以添加关键字投票和相应地址访问微信时可以获取code

    public function getcode(){
    	$code=$_GET['code'];//预定义$_GET变量用于收集来自method="get"的表单中的值
    	// echo $code;
    	$json = $this->access_token($code);
    	echo $json;
    }
    //获取access_token
    private function access_token($code){
    	$appid="wx7e35296d7fd50349";
    	$appsecret="7313d506cd98681236061585c3cbb1f1";
 
    	$url="https://api.weixin.qq.com/sns/oauth2/access_token?appid=$appid&secret=$appsecret&code=$code&grant_type=authorization_code";
 
    	$ret=https_request($url);
    	return $ret;
    }