private void btn_Sent_Click(object sender, RoutedEventArgs e) { var isAuthenticated = _clientTcp.IsAuthenticated(); if (!isAuthenticated || string.IsNullOrWhiteSpace(textSent.Text)) { return; } var selectedConversation = (ConversationModel)listBox.SelectedItem; if (selectedConversation != null) { var message = new MessageEventArgsModel { Text = textSent.Text, MessageType = MessageType.ToAnotherClient, ConversationId = selectedConversation.Id, ClientId = _currentСlient.Id, PostingDateTime = DateTime.Now }; var messageId = _common.SaveMessage(message); message.Id = messageId; _clientTcp.SentMessage(message); textSent.Text = string.Empty; } }