/// <summary>
/// 每当客户端连接时
/// </summary>
/// <param name="listener"></param>
/// <param name="connected"></param>
/// <returns></returns>
public static Task <TcpListener> WheneverTcpClientConnected(this TcpListener listener, Action <TcpClient> connected)
{
return(listener.WheneverTcpClientConnected(connected, CancellationToken.None));
}