PHP 封装微信网页授权（OAuth2.0）开发指南

<?php

/**
 * 微信网页授权核心处理类
 */
class Wechat {
  
  // 【必填】请在下方填入你在微信公众平台获取的真实凭证
  private $app_id = 'YOUR_APP_ID';
  private $app_secret = 'YOUR_APP_SECRET';

  /**
   * 获取微信授权链接
   * @param string $redirect_uri 授权回调地址（建议绝对路径）
   * @param string $state 状态码，用于防止 CSRF 攻击
   */
  public function get_authorize_url($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";
  }

  /**
   * 根据 code 换取网页授权 access_token
   */
  public function get_access_token($code = '') {
    if (empty($code)) return false;

    $token_url = "https://api.weixin.qq.com/sns/oauth2/access_token?appid={$this->app_id}&secret={$this->app_secret}&code={$code}&grant_type=authorization_code";
    $token_data = $this->http($token_url, 'GET');

    if ($token_data['code'] == 200) {
      return json_decode($token_data['body'], TRUE);
    }
    return FALSE;
  }

  /**
   * 获取授权后的微信用户信息
   */
  public function get_user_info($access_token = '', $open_id = '') {
    if (!$access_token || !$open_id) return FALSE;

    $info_url = "https://api.weixin.qq.com/sns/userinfo?access_token={$access_token}&openid={$open_id}&lang=zh_CN";
    $info_data = $this->http($info_url, 'GET');

    if ($info_data['code'] == 200) {
      return json_decode($info_data['body'], TRUE);
    }
    return FALSE;
  }

  /**
   * 底层 HTTP 请求封装
   */
  private 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($ci, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ci, CURLOPT_SSL_VERIFYPEER, FALSE);
    curl_setopt($ci, CURLOPT_SSL_VERIFYHOST, FALSE);

    switch ($method) {
      case 'POST':
        curl_setopt($ci, CURLOPT_POST, true);
        if (!empty($postfields)) {
          curl_setopt($ci, CURLOPT_POSTFIELDS, $postfields);
        }
        break;
    }
    curl_setopt($ci, CURLOPT_URL, $url);
    curl_setopt($ci, CURLOPT_HTTPHEADER, $headers);

    $response = curl_exec($ci);
    $http_code = curl_getinfo($ci, CURLINFO_HTTP_CODE);

    curl_close($ci);
    return array('code' => $http_code, 'body' => $response);
  }
}
<?php