这个问题真的没有解释太多，但猜测一点点，这样做应该做（我不熟悉旧的api，所以我不知道你是否必须传递任何参数update_user_is_connected / not_connected，相应地修改）：

  window.fbAsyncInit = function（）{
 FB.init（{
 appId：'<％= ConfigurationManager.AppSettings [ ApiKey]。ToString（）％>'，
 status：true，//检查登录状态
 cookie：true，//启用Cookie以允许服务器访问会话
 xfbml ：true，// parse XFBML 
 channelUrl：'http://www.yourdomain.com/channel.html'，//自定义渠道网址
 oauth：true //启用OAuth 2.0 
 }）; 

 FB.getLoginStatus（function（response）{
 if（response.authResponse）update_user_is_connected（）; 
 else update_user_is_not_connected（）; 
}）; 

 //一旦用户登录到Facebook（通过您的站点）
 FB.Event.subscribe（'auth.login'，function（response）{
 update_user_is_connected（）; 
}）; 
}; 
 

您可以阅读更多信息：

http://developers.facebook.com/docs/reference/javascript/FB。 getLoginStatus /

I am new to Facebook implementation . Please help me to implement this code through new all.js using OAuth2.0

 window.addEvent('domready', function(){     
 FB.init("<%= ConfigurationManager.AppSettings["ApiKey"].ToString() %>", 
         "/xd_receiver.htm",
         {"ifUserConnected": update_user_is_connected,
          "ifUserNotConnected": update_user_is_not_connected,
          "doNotUseCachedConnectState":"true"});
});

The question doesn't really explain much, but guessing a little bit, something like this should do (I'm not familiar with the old api, so I don't know whether you have to pass any arguments to update_user_is_connected/not_connected, modify that accordingly):

window.fbAsyncInit = function() {
    FB.init({
        appId  : '<%= ConfigurationManager.AppSettings["ApiKey"].ToString() %>',
        status : true, // check login status
        cookie : true, // enable cookies to allow the server to access the session
        xfbml  : true,  // parse XFBML
        channelUrl  : 'http://www.yourdomain.com/channel.html', // Custom Channel URL
        oauth : true //enables OAuth 2.0
    });

    FB.getLoginStatus(function(response) {
        if (response.authResponse) update_user_is_connected();
        else update_user_is_not_connected();
    });

    // This will be triggered as soon as the user logs into Facebook (through your site)
    FB.Event.subscribe('auth.login', function(response) {
        update_user_is_connected();
    });
};

You can read more at:

http://developers.facebook.com/docs/reference/javascript/FB.getLoginStatus/