新中新二代身份证读卡Syn_ReadBaseMsg方法

新中新二代身份证读卡器dkq-a16d，在C#中读卡开发时，参考随机附带的C#参考代码，能够读取成功，但读几次程序就莫名其妙的关掉了，有时连错误都捕捉不到，搞了很长时间也没搞定，后来以为会不会是win7系统支持不好，就在XP系统中继续鼓捣，问题依旧。
　　后来不相信，直接使用其自带的一个读卡程序以及其他语言开发的测试，都会出现这种问题，有时候读不到10次，有时候多几次，也会自动关闭程序。而出现这种情况，全部是通过调用支持动态库中的Syn_ReadMsg函数进行读取的，这说明此函数本身有问题。最后改成调用Syn_ReadBaseMsg函数，就解决了这个莫名其妙的问题。
　　Syn_ReadBaseMsg函数与Syn_ReadMsg函数的区别是，后者是直接将读出的信息进行了格式化（以结构体返回）并生成了图片文件，而前者是通过将信息和图片以2个指针返回，需要开发人员自行处理。

　　以下是相关函数代码，仅供参考。


        [DllImport("SynIDCardAPI.dll", EntryPoint = "Syn_ReadBaseMsg", CharSet = CharSet.Ansi)]
        public static extern int Syn_ReadBaseMsg(int iPort, IntPtr pucCHMsg, ref uint puiCHMsgLen, IntPtr pucPHMsg, ref uint puiPHMsgLen, int iIfOpen);

        ///

        /// 读取身份证基本信息
        ///

        ///
        ///
        ///
        public static bool ReadCard(out ZbsoftInterface.IDCardData CardMsg,
            out string errStr)
        {
            CardMsg = new ZbsoftInterface.IDCardData();
            errStr = "";
            int nRet;
            byte[] pucIIN = new byte[4];
            byte[] pucSN = new byte[8];

            #region 获取读卡器
            if (nPort == 0)
            {
                if (!FindDrivers(out errStr))
                {
                    if (string.IsNullOrEmpty(errStr))
                        errStr = "没有找到读卡器";
                    return false;
                }
            }
            #endregion

            if (Syn_OpenPort(nPort) == 0)
            {
                if (Syn_SetMaxRFByte(nPort, 80, 0) == 0)
                {
                    nRet = Syn_StartFindIDCard(nPort, ref pucIIN[0], 0);
                    nRet = Syn_SelectIDCard(nPort, ref pucSN[0], 0);
                    string cardMsg = new string(' ', 256);  //身份证基本信息返回长度为256
                    string imgMsg = new string(' ', 1024);  //身份证图片信息返回长度为1024
                    IntPtr msg = Marshal.StringToHGlobalAnsi(cardMsg);  //身份证基本信息
                    IntPtr img = Marshal.StringToHGlobalAnsi(imgMsg);   //身份证图片
                    try
                    {
                        uint mLen = 0;
                        uint iLen = 0;
                        nRet = Syn_ReadBaseMsg(nPort, msg, ref mLen, img, ref iLen, 0);
                        if (nRet == 0)
                        {
                            string card = Marshal.PtrToStringUni(msg);
                            char[] cartb = card.ToCharArray();
                            CardMsg.Name = (new string(cartb, 0, 15)).Trim();
                            CardMsg.Sex = new string(cartb, 15, 1);
                            CardMsg.Nation = new string(cartb, 16, 2);
                            CardMsg.Born = new string(cartb, 18, 8);
                            CardMsg.Address = (new string(cartb, 26, 35)).Trim();
                            CardMsg.IDCardNo = new string(cartb, 61, 18);
                            CardMsg.GrantDept = (new string(cartb, 79, 15)).Trim();
                            CardMsg.UserLifeBegin = new string(cartb, 94, 8);
                            CardMsg.UserLifeEnd = new string(cartb, 102, 8);
                            return true;
                        }
                        else
                        {
                            errStr = "读取身份证信息错误";
                        }
                    }
                    catch (Exception e) { errStr = e.Message; }
                    finally
                    {
                        Marshal.FreeHGlobal(msg);
                        Marshal.FreeHGlobal(img);
                    }
                }
                else
                {
                    errStr = "SetMaxRFByte出错";
                }
            }
            else
            {
                errStr = "打开端口失败";
            }
            return false;
        }

        ///

        /// 自动查询读卡器
        ///

        /// 错误信息
        ///
        public static bool FindDrivers(out string err)
        {
            int i = 0;
            err = "";
            try
            {
                i = Syn_FindReader();
            }
            catch (Exception e)
            {
                err = e.ToString();
                return false;
            }
            if (i > 0)
            {
                nPort = i;
            }
            else
            {
                nPort = 0;
                return false;
            }
            return true;
        }