微信view类型的菜单获取openid范例

<?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
}

?>