C#

willington.d wrote:

How to do this in c#? Is there any Namespase or thrd party dll available?

private SerialPort _port;       //Serial port (USB)
const int BAUDRATE = 9600;      //Baud-Rate of the serial port (must be the same value on the other device)
const string COMPORT = "COM8";  //Name of the port
delegate void DisplayArduinoSerialOutput(string arduinoSerialOutput); //Delegate to display the serial input buffers' content to the User

/// <summary>
/// This method initializes the COM-Port
/// </summary>
private void InitCOMPort()
{
   _port = new SerialPort(COMPORT) { BaudRate = BAUDRATE };
   //Event occurs when any data arrives at the port
   _port.DataReceived += new   SerialDataReceivedEventHandler(_port_DataReceived); 
   //Open the port 
   //An exception can rise if another program blocked
   //the port
   _port.Open();
}

/// <summary>
/// Occurs when new data is available at the ports input buffer
/// </summary>
/// <param name="sender">the sender of the event (usually the port)</param>
/// <param name="e">Some event args, not used at the moment</param>
private void _port_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
   DisplayArduinoSerialOutput displayArduinoSerialOutput = new DisplayArduinoSerialOutput(arduinoSerialOutputTextBox.AppendText);
   SerialPort spL = (SerialPort)sender;
   this.Dispatcher.Invoke(displayArduinoSerialOutput, spL.ReadExisting());
}

Marco Bertschi wrote:

const string COMPORT = "COM8";

Quote:

A first chance exception of type 'System.AccessViolationException' occurred in mscorlib.dll
The thread 'vshost.RunParkingWindow' (0x518) has exited with code 0 (0x0).
The thread '<no name="">' (0x1fdc) has exited with code 0 (0x0).
The program '[7952] CLCLis.vshost.exe: Managed (v2.0.50727)' has exited with code 0 (0x0).
The program '[7952] CLCLis.vshost.exe: Program Trace' has exited with code 0 (0x0).

taibc wrote:

How I can trace the error through source codes while I am using dll file ?

taibc wrote:

I think the source codes don't have error

• Defining the fields in the struct in a different order definitely won't work. You need to declare in the same order (hopefully the reason for this is obvious).
• You've defined it as a class in C#, not a struct. I think you need it to be a struct, even though it's a pointer type declaration in C++. You might even need to declare it IntPtr and use Marshal methods to make a struct out of it.
• What is DGNHandle? That C++ function definition isn't valid unless it's a macro.

[DllImport("DgnLib.dll", EntryPoint = "DGNReadElement")]
        public static extern IntPtr DGNReadElement(IntPtr DGNHandle);

        public static DGNElemCore ReadElement(IntPtr DGNHandle)
        {

            DGNElemCore element = new DGNElemCore ();
            IntPtr itr = DGNReadElement(DGNHandle);

            element = (DGNElemCore)Marshal.PtrToStructure(itr, typeof(DGNElemCore)); // throw the exception

            return element;

        }

__declspec(dllexport) DGNElemCore CPL_DLL *DGNReadElement( DGNHandle );

struct DGNElemText
{
   .....

   char text[1]; /*!< Actual text (length varies, \0   terminated*/ 

   ....
}

[StructLayout(LayoutKind.Sequential)]
public class DGNElemText
{
   .....

   IntPtr text; 
}

[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 1)]
public string text; 

__declspec(dllexport) DGNElemCore CPL_DLL *DGNReadElement( DGNHandle );

[DllImport("DgnLib.dll", EntryPoint = "DGNReadElement")]              
        public static extern IntPtr DGNReadElement(IntPtr DGNHandle);    
 public static DGNElemCore ReadElement(IntPtr DGNHandle)
        {
            DGNElemCore element = new DGNElemCore ();
            IntPtr itr = DGNReadElement(DGNHandle);
            MessageBox.Show(itr.GetType ().ToString ());

            element = (DGNElemCore)Marshal.PtrToStructure(itr, typeof(DGNElemCore));                          
            return element;            
        }

DGNElemCore element = new DGNElemCore();
element = DgnFile.ReadElement(DGNHandle);

while (element != null) 
{
    if (element.type == 17 ) // Element is a DGNElemText 
    {
         DGNElemText txtElement = new DGNElemText();
         txtElement = (DGNElemText)element; **// throw error: Unable to cast object of type DgnLib.DGNElemCore to type DgnLib.DGNElemText**

         ...... // More codes

    }
}

[StructLayout(LayoutKind.Sequential )]
    public class DGNElemCore
    {
        public int offset;
        public int size;
        public int element_id;
        public int stype;
        public int level;
        public int type;
        public int complex;
        public int deleted;
        public int graphic_group;
        public int properties;
        public int color;
        public int weight;
        public int style;
        public int attr_bytes;
        public IntPtr attr_data;
        public int raw_bytes;
        public IntPtr raw_data;

    }

[StructLayout (LayoutKind.Sequential)]
    public class DGNElemText : DGNElemCore
    {
        // Fields
        DGNElemCore core;

        public int font_id;
        public int justification;
        public double length_mult;
        public double height_mult;
        public double rotation;
        public DGNPoint origin;
        public string text;
    }