一段时间不活动后，SignalR JavaScript集线器方法未在IE中触发

Question

I have a SignalR (v0.5.2) Hub sending a message to a JavaScript client.

c#

public Task SendData(ClassName classData){
    return Clients["groupid"].renderData(classData);
}

javascript

var _client = $.connection.myHub;
_client.renderData = function(data){
    /* do stuff */
};

$.connection.hub.start({ transport:activeTransport }, function(){ });

All works fine except that after a period of inactivity in IE9, the JavaScript method fails to run.

I have looked at the Response Body of the /signalr/connect?transport=foreverFrame network log within IE9 developer tools and can see that I am receiving the message:

<script>r(c, {"MessageId":"54","Messages":[{"Hub":"myHub","Method":"renderData","Args":[....]]}],"Disconnect":false,"TimedOut":false,"TransportData":{"Groups":["LiveBid.999"]}});</script>
<div>{"MessageId":"54","Messages":[{"Hub":"myHub","Method":"renderData","Args":[....]]}],"Disconnect":false,"TimedOut":false,"TransportData":{"Groups":["LiveBid.999"]}}</div>

Yet the JavaScript method never fires?

Answer 1

After a lot of time spent debugging this, it turns out that it is the version of my Modernizr file which is causing the problem.

I am not massively familiar with how the inners of Modernizer work, however I have created a custom version of the file that only has css/html5 elements features, and this currently seems to work with SignalR and foreverFrame.