/// <summary>
/// Отправка сообщений по клавише Enter
/// </summary>
private async void MessageTextBox_KeyDown(object sender, System.Windows.Input.KeyEventArgs e)
{
if (messageTextBox.Text.Length > 0 && e.Key == Key.Enter)
{
await client.SendMessageAsync(messageTextBox.Text);
messageTextBox.Text = "";
}
}