/// <summary>
    /// 呼叫
    /// </summary>
    /// <param name="callID">呼叫ID</param>
    /// <param name="type">呼叫类型 1:音频 2:视频</param>
    /// <param name="from">呼叫者 ID</param>
    /// <param name="to">被呼叫者ID </param>
    public void Call(string callID, ChatType type, int from, int to)
    {
        if (CallID == "")
        {
            CallID = callID;
            ProtocolDataModel pd = new ProtocolDataModel();
            pd.Type    = ProtocolType.TYPE_IM;
            pd.Request = IMProtocol.IM_CALL_CRE;

            IMInfo info = new IMInfo();
            info.UserName = UserName;
            info.UserID   = UserID;
            info.CallID   = callID;
            info.CallType = (int)type;

            ChatDataHandler.Instance.ChatType = type;

            info.PeerID = to;
            ChatPeerID  = to;

            using (MemoryStream stream = new MemoryStream())
            {
                info.WriteTo(stream);
                pd.Message = stream.ToArray();
            }
            NetWorkManager.Instance.Send(pd);
        }
    }
    /// <summary>
    /// 挂断
    /// </summary>
    public void Hang()
    {
        if (CallID != "")
        {
            CallID = "";
            ProtocolDataModel pd = new ProtocolDataModel();
            pd.Type    = ProtocolType.TYPE_IM;
            pd.Request = IMProtocol.IM_HANG_CRES;

            IMInfo info = new IMInfo();
            info.PeerID = ChatPeerID;
            using (MemoryStream stream = new MemoryStream())
            {
                info.WriteTo(stream);
                pd.Message = stream.ToArray();
            }
            NetWorkManager.Instance.Send(pd);
            //结束udp传输
            ChatDataHandler.Instance.StopChat();
        }
    }
    /// <summary>
    /// 接听
    /// </summary>
    public void Accept()
    {
        ProtocolDataModel pd = new ProtocolDataModel();

        pd.Type    = ProtocolType.TYPE_IM;
        pd.Request = IMProtocol.IM_ACCEPT_CRES;

        IMInfo info = new IMInfo();

        info.UserName = UserName;
        info.UserID   = UserID;
        info.PeerID   = ChatPeerID;
        //info.CallType = type;
        using (MemoryStream stream = new MemoryStream())
        {
            info.WriteTo(stream);
            pd.Message = stream.ToArray();
        }
        NetWorkManager.Instance.Send(pd);

        //开始udp传输
        ChatDataHandler.Instance.StartChat();
    }