我调用BeginReceive()在这样一个SubscriptionClient:)天青ServiceBus SubscriptionClient.EndReceive()返回null
client.BeginReceive(new TimeSpan(6, 0, 0), new AsyncCallback(DownloadResults), null);
而在DownloadResults(回调我叫client.EndReceive()客户端是一个静态成员类]的
static public void DownloadResults(IAsyncResult ar)
{
// Get the message from the service bus.
msg = client.EndReceive(ar);
if (msg == null)
{
Console.WriteLine("Error!");
return;
}
}
有时client.EndReceive()返回null
。通过查看SubscriptionClient.EndReceive()的MSDN页面,我不清楚什么时候EndReceive()返回null
。是否因为我在BeginReceive()中指定的时间限制已超出?还是因为有错误?