MFC dll in c# web Application RSS

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  cathie16

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  MFC dll in c# web Application

  Aug 06, 2011 02:15 PM|LINK

  I have a MFC dll which is used for scanning a document from scanner and i want to use that dll in web application for scan and uploading a document.I am not familier with MFC .Is it possible to refer th MFC dll?

  I tried referring the dll but when i run it im getting error "External Component throws an exception".i would be very thankful if any1 could help me on this.

   

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  ignatandrei

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  Re: MFC dll in c# web Application

  Aug 06, 2011 08:40 PM|LINK

  Depends if the dll have a COM interface or exports a function.

  If it is a COM, just reference that.

  If not, you should use DLLIMport for the function of the dll. See http://msdn.microsoft.com/en-us/library/aa288468%28v=vs.71%29.aspx

  My .NET blog : http://msprogrammer.serviciipeweb.ro/ |2012 Programmer tools
  • Marked as answer by cathie16 on Aug 11, 2011 05:34 AM
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  cathie16

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  Re: MFC dll in c# web Application

  Aug 07, 2011 07:03 AM|LINK

  I am using the dll to call a function.Now the error im getting is

  A call to PInvoke function 'App_Code.tvheafo_!Scancsharp+UnsafeNativeMethods::getpath' has unbalanced the stack. This is likely because the managed PInvoke signature does not match the unmanaged target signature. Check that the calling convention and parameters of the PInvoke signature match the target unmanaged signature.

  this is the code used for calling the function

  string cs = Scancsharp.UnsafeNativeMethods.getpath(file);

  this is the code im using to define the function in dll

    [DllImport(_dllLocation)]
          [return: MarshalAs(UnmanagedType.LPStr)]
          public static extern string getpath([MarshalAs(UnmanagedType.LPStr)]  string name);

   this is function definition in dll

  extern "C" __declspec(dllexport) LPTSTR getpath(LPSTR aFilePath)
  	{
  coding...
  }

  What wrong am i doing? 

  • Edited by cathie16 on Aug 07, 2011 07:04 AM
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  cathie16

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  Re: MFC dll in c# web Application

  Aug 11, 2011 05:34 AM|LINK

  I got the solution.

  The call to MFC dll sholud like this:

  [DllImport(_dllLocation, CallingConvention = CallingConvention.Cdecl)]
          [return: MarshalAs(UnmanagedType.LPStr)]
          public  static extern   string getpath([MarshalAs(UnmanagedType.LPStr)]  string name);

  Thanks for the help.

  • Marked as answer by cathie16 on Aug 11, 2011 05:34 AM