php 微信扫码登录网站

前期准备：
微信开放平台：https://open.weixin.qq.com/

前端代码：

<a   onclick='towxLogin()' openwindowheight="520" openwindowwidth="450" data-third="weixin" class="wx icon" pbtag="微信" pbflag="头部" title="微信登录"></a>
<div id="login_container" style="z-index: 99999;position: absolute;background-color: white;"></div>
js拉起微信登录使div浮于最上层

<script type="text/javascript" src="https://res.wx.qq.com/connect/zh_CN/htmledition/js/wxLogin.js"></script>  
<script type="text/javascript">
     
    function towxLogin()
    { 
        var obj = new WxLogin({
         self_redirect:false, //false 登录之后的页面不在frame内打开，在最上层打开
         id:"login_container", 
         appid: "APPID", 
         scope: "snsapi_login", 
         redirect_uri: "{$wxCallback}", //带协议的完整的登录回调地址
         state: "sf_Wxlogin",
         style: "black",
         href: ""
         });
    } 
    
   
</script>

后端代码：

    public function wechat_login()
    { 
        $wxConfig = C('THINK_SDK_WEIXIN'); 
        $appid     = $wxConfig['APP_KEY']; 
        $appsecret = $wxConfig['APP_SECRET'];
   
        $auth  = new WechatAuth($appid, $appsecret);
        $token = $auth->getAccessToken("code",$_GET['code']);
 

        $userInfo = $auth->getUserInfo($token['openid']); 

        
		//获取用户信息成功后的内部操作
     
     }