InvalidOperationException with BeginGetRequestStream

本文关键字：BeginGetRequestStream with InvalidOperationException | 更新日期: 2023-09-27 17:53:51

我得到以下错误:

System.InvalidOperationException was unhandled by user code
  HResult=-2146233079
  Message=Operation is not valid due to the current state of the object.
  Source=System.Windows
  StackTrace:
       at System.Net.Browser.ClientHttpWebRequest.InternalEndGetRequestStream(IAsyncResult asyncResult)
       at System.Net.Browser.ClientHttpWebRequest.EndGetRequestStream(IAsyncResult asyncResult)
       at SophosMobileControl.MainPage.<>c__DisplayClass5.<PushTestButton_Click>b__3(IAsyncResult ar)
       at System.Net.Browser.ClientHttpWebRequest.<>c__DisplayClass18.<InvokeGetRequestStreamCallback>b__16(Object state2)
  InnerException:

与以下代码:

// Get the URI that the Microsoft Push Notification Service returns to the push client when creating a notification channel.
            // Normally, a web service would listen for URIs coming from the web client and maintain a list of URIs to send
            // notifications out to.
            string subscriptionUri = (App.Current.Resources["Locator"] as ViewModelLocator).Main.PushUri;
            HttpWebRequest sendNotificationRequest = (HttpWebRequest)WebRequest.Create(subscriptionUri);
            // Create an HTTPWebRequest that posts the toast notification to the Microsoft Push Notification Service.
            // HTTP POST is the only method allowed to send the notification.
            sendNotificationRequest.Method = "POST";
            // Create the toast message.
            string toastMessage = "<?xml version='"1.0'" encoding='"utf-8'"?>" +
            "<wp:Notification xmlns:wp='"WPNotification'">" +
               "<wp:Toast>" +
                    "<wp:Text1>" + "Title" + "</wp:Text1>" +
                    "<wp:Text2>" + "Subtitle" + "</wp:Text2>" +                        
               "</wp:Toast> " +
            "</wp:Notification>";
            // Set the notification payload to send.
            byte[] notificationMessage = Encoding.UTF8.GetBytes(toastMessage);
            // Set the web request content length.
            sendNotificationRequest.ContentLength = notificationMessage.Length;
            sendNotificationRequest.ContentType = "text/xml";
            //sendNotificationRequest.Headers["X-WindowsPhone-Target"] = "toast";
            //sendNotificationRequest.Headers["X-NotificationClass"] = "2";
            sendNotificationRequest.BeginGetRequestStream(ar =>
            {
                using (Stream postStream = sendNotificationRequest.EndGetRequestStream(ar))
                {
                    postStream.Write(notificationMessage, 0, notificationMessage.Length);
                }
            }, sendNotificationRequest);

InvalidOperationException with BeginGetRequestStream

我的解决方案是更改以下代码:

        sendNotificationRequest.BeginGetRequestStream(ar =>
        {
            using (Stream postStream = sendNotificationRequest.EndGetRequestStream(ar))
            {
                postStream.Write(notificationMessage, 0, notificationMessage.Length);
            }
        }, sendNotificationRequest);

由:

    sendNotificationRequest.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), sendNotificationRequest);
    void GetRequestStreamCallback(IAsyncResult callbackResult)
    {
        HttpWebRequest myRequest = (HttpWebRequest)callbackResult.AsyncState;
        // End the stream request operation
        Stream postStream = myRequest.EndGetRequestStream(callbackResult);
        // Add the post data to the web request
        postStream.Write(notificationMessage, 0, notificationMessage.Length);
        postStream.Close();
    }