使用 ZKemKeeper.DLL 时出现错误代码 -201

Question

我正在使用 ZKemKeeper.DLL 创建 C# WinForm 以从生物识别设备中获取数据。但是当我尝试将我的应用程序连接到设备时，它总是给出错误代码 -201

知道是什么原因造成的吗？我已经阅读了 ZKemKeeper.DLL 的指南文档，但它没有将 -201 列为错误代码。任何帮助将非常感激。谢谢。

private void btnConnect_Click(object sender, EventArgs e)
        {
            try
            {
                IsConnected = TimeKeeper.Connect_Net(txtIP.Text, 4370);
                if (IsConnected == true)
                {
                    MessageBox.Show("Device Connected Successfully.");
                }
                else
                {
                    TimeKeeper.GetLastError(ref ErrorCode);
                    MessageBox.Show("Device Not Found. Error Code : " + ErrorCode.ToString(), "Error");
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
        }

Answer 1

protected void btnConnect_Click(object sender, EventArgs e)
        {
            try
            {
                //this.Cursor = Cursors.WaitCursor;
                //ShowStatusBar(string.Empty, true);

            if (IsDeviceConnected)
            {
                IsDeviceConnected = false;
                //this.Cursor = Cursors.Default;

                return;
            }

            string ipAddress = txtIPAddress.Text.Trim();
            string port = txtPort.Text.Trim();
            if (ipAddress == string.Empty || port == string.Empty)
                throw new Exception("The Device IP Address and Port is mandotory !!");

            int portNumber = 4370;
            if (!int.TryParse(port, out portNumber))
                throw new Exception("Not a valid port number");

            bool isValidIpA = UniversalStatic.ValidateIP(ipAddress);
            if (!isValidIpA)
                throw new Exception("The Device IP is invalid !!");

            isValidIpA = UniversalStatic.PingTheDevice(ipAddress);
            if (!isValidIpA)
                throw new Exception("The device at " + ipAddress + ":" + port + " did not respond!!");

            objZkeeper = new ZkemClient(RaiseDeviceEvent);
            IsDeviceConnected = objZkeeper.Connect_Net(ipAddress, portNumber);

            if (IsDeviceConnected)
            {
                string deviceInfo = manipulator.FetchDeviceInfo(objZkeeper, int.Parse(txtMachineNumber.Text.Trim()));
                //lblDeviceInfo.Text = deviceInfo;

                lblMessage.Text = deviceInfo + "is Connected";
            }

        }
        catch (Exception ex)
        {
            throw(ex);
        }
        //this.Cursor = Cursors.Default;
    }