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        private async void button_Click(object sender, RoutedEventArgs e)
        {
            var t = Task.Run(() =>
            {
                // SQL Abfrage, was auch immer
                return DoProcessing();
            });
            await t;
            MessageBox.Show("Ergebnis: " + t.Result);
        }

        private int DoProcessing()
        {
            Thread.Sleep(1000);
            return 42;
        }					

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private async void CheckForNews()
        {
            var t = Task.Run(() =>
            {

                MessageBox.Show("Test");
                int i = 0;
                string URL = "Die URL";
                WebClient webClient = new WebClient();
                NameValueCollection formData = new NameValueCollection();
                formData["username"] = Benutzername;
                formData["action"] = "ungelesen";

                byte[] responseBytes = webClient.UploadValues(URL, "POST", formData);
                string responsefromserver = Encoding.UTF8.GetString(responseBytes);
                webClient.Dispose();
                string[] AlleNachrichten = responsefromserver.Split('|');
                foreach (string allenachrichten in AlleNachrichten)
                    i++;

                i--;
                if (i > MaxNewMessage)
                {
                    MaxNewMessage = i;
                    this.button1.Text = "meine Nachrichten  [" + MaxNewMessage.ToString() + "]";
                }
                else if (i == MaxNewMessage)
                    this.button1.Text = "meine Nachrichten  [" + MaxNewMessage.ToString() + "]";
                else
                    this.button1.Text = "meine Nachrichten";
            });
            await t;

            System.Threading.Thread.Sleep(5000);
        }					

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        private async Task<int> GetMessageCount()
        {
            NameValueCollection formData = new NameValueCollection();
            formData["username"] = Benutzername;
            formData["action"] = "ungelesen";

            byte[] responseBytes;
            using (var wc = new WebClient())
                responseBytes = await wc.UploadValuesTaskAsync("http://meineadresse.de", WebRequestMethods.Http.Post, formData);

            var response = Encoding.UTF8.GetString(responseBytes);
            var allMessages = response.Split('|');

            return allMessages.Length;
        }

        private async Task CheckForNewMessages()
        {
            var messageCount = await GetMessageCount();
            button1.Text = messageCount >= maxMessageCount ? $"meine Nachrichten [{messageCount}]" : "meine Nachrichten";
            if (messageCount > maxMessageCount)
                maxMessageCount = messageCount;
        }

        private async void button1_Click(object sender, EventArgs e)
        {
            await CheckForNewMessages();
        }