我調用BeginReceive()在這樣一個SubscriptionClient:)天青ServiceBus SubscriptionClient.EndReceive()返回null
client.BeginReceive(new TimeSpan(6, 0, 0), new AsyncCallback(DownloadResults), null);
而在DownloadResults(回調我叫client.EndReceive()客戶端是一個靜態成員類]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;
}
}
有時client.EndReceive()返回null
。通過查看SubscriptionClient.EndReceive()的MSDN頁面,我不清楚什麼時候EndReceive()返回null
。是否因爲我在BeginReceive()中指定的時間限制已超出?還是因爲有錯誤?