php微信授权获取openid

<?php include_once 'config.php'; $code = $_GET['code']; $url = "https://api.weixin.qq.com/sns/oauth2/access_token?appid=" . $appid . "&secret=" . $secret . "&code=" . $code . "&grant_type=authorization_code"; $ch = curl_init(); curl_setopt($ch, CURLOPT_POST, 1); curl_setopt($ch, CURLOPT_HEADER, 0); curl_setopt($ch, CURLOPT_URL, $url); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); $result = curl_exec($ch); curl_close($ch); $rs = $result ? json_decode($result, true) : ""; $_SESSION['openid'] = $rs['openid']; $url_current = $_SESSION['url_current'] ? $_SESSION['url_current'] : "http://www.erdangjiade.com/"; header("Location: " . $url_current . "");