在程序中调用C++链接库中的回调函由于没有考虑生命周期，直接写委托回随机的被gc给回收掉导致报这个错误

错误的程序:

private void InitPlateIdentify()

{

   try

   {

        if (string.IsNullOrEmpty(sPlateIP))return;

        handle = Dbvt_JpegCreateCamera(handle);

        Dbvt_JpegSetCameraCallBack(handle,DBVT_JpegSave,DBVT_GetSerialData,Dbvt_SetDevicesError);

        if (!Dbvt_JpegConnectDataCamera(handle, sPlateIP))

                    MessageBox.Show("打开车牌识别失败");

       }

       catch (Exception ex)

       {

           MessageBox.Show("打开车牌识别失败");

           Log.log("错误InitPlateIdentify:" + ex.ToString());

       }

 }

正确的程序:

private CameraJpegCallBackFunc fMSGCallBack;

private void InitPlateIdentify()

{

     try

     {

          if (string.IsNullOrEmpty(sPlateIP)) return;

          this.fMSGCallBack = this.DBVT_JpegSave;

          handle = Dbvt_JpegCreateCamera(handle);

          Dbvt_JpegSetCameraCallBack(handle, this.fMSGCallBack, DBVT_GetSerialData, Dbvt_SetDevicesError);

           if (!Dbvt_JpegConnectDataCamera(handle, sPlateIP))

                    MessageBox.Show("打开车牌识别失败");

       }

       catch (Exception ex)

       {

           MessageBox.Show("打开车牌识别失败");

                Log.log("错误InitPlateIdentify:" + ex.ToString());

        }

}