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C# dll called from C++ app GPF

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  4 years ago

  by Al_Pennyworth

  Al_Pennyworth

  , United States

  Joined 7 years ago

  This is a little difficult to explain. I created a dll in .NET using C# and I need to call this dll from a Visual C++ 6.0 application. I read numerous materials on setting the C# dll up with COM Interop and I think I have it working. Now for the difficult part: when I call the function to launch the UI in the C# dll, it comes up, then I do my thing and close it down. I then go through the functionality again and the dll is called w/ no problems, the form comes up, etc. When I close it down, I will get a GPF. In trying to trace the problem, it returns from my dll, then returns from my function in the 6.0 c++ application, and returns from another function. I cannot discover where the GPF is occurring. Here is a basic outline of my 6.0 c++ function:
  

  
  void functionname
  {
  // Initialize COM.
  HRESULT hr = CoInitialize(NULL);
  

  
  // Create the interface pointer.
  IManageInterfacePtr pIInterface(__uuidof(ManagerInterface));
  

  
  // Call the Add method.
  pIInterface->LaunchRSSDLL(string, string, string);
  

  
  pIInterface->Dispose(); <--this is from trying something with the C# dll
  

  
  pIInterface->Release();
  

  
  // Uninitialize COM.
  CoUninitialize();
  }
  

  
  I have put try/catch inside this function, around the call to this function, inside my C# DLL COM interface, and I still cannot find where the gpf is occurring. This is my first C# dll so be please be patient if I so kind of idiotic in describing this. Any ideas on what I may be missing? Any ideas on what I can look at?
  

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  4 years ago

  by Al_Pennyworth

  Al_Pennyworth

  , United States

  Joined 7 years ago

  I found the answer to my problem:
  

  
  http://www.dotnet247.com/247referen.../35/178790.aspx
  

  
  I removed the EnableVisualStyles() call from my .NET dll and the unhandled exception has not been encountered.
  

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  4 years ago

  by wdli

  David Li

  Sunnyvale, CA, United States

  Joined 4 years ago
  Hello,
  
  I am facing a similiar problem but haven't figured out about it. Maybe you can help or share the experience:
  
  
  This is my problem:
  
  I have C# project compiled as a DLL. The C# class is defined as:
  
  public Cs_Class
  {
  String name;
  public Cs_Class(String n)
  { name = n; }
  
  ....
  }
  
  I have another MC++ project that uses the DLL. The MC++ class is defined as:
  
  public Cpp_Class
  {
    ....
    void Test(String* testStr)
    {
          //Create the c# class
          //
          Cs_Class* c = new Cs_Class(testStr);
    }
  
  }
  
  
  The compilation/linking was fine. I then encountered a run-time exception:
  
  System.MissingMethodException: Method not found: Cs_Class..ctor(System.String)...
  
  Strangly enough, if I took out the String parameter in Cs_Class constructor and not pass in String* in MC++ class when constructing the Cs_Class object, then everything was fine.
  
  Why??
  
  Thanks in advance.
  
  David
  
  
  
  
  Quote:

  [1]Posted by Al_Pennyworth on 17 Mar 2005 06:15 PM[/1]
  This is a little difficult to explain. I created a dll in .NET using C# and I need to call this dll from a Visual C++ 6.0 application. I read numerous materials on setting the C# dll up with COM Interop and I think I have it working. Now for the difficult part: when I call the function to launch the UI in the C# dll, it comes up, then I do my thing and close it down. I then go through the functionality again and the dll is called w/ no problems, the form comes up, etc. When I close it down, I will get a GPF. In trying to trace the problem, it returns from my dll, then returns from my function in the 6.0 c++ application, and returns from another function. I cannot discover where the GPF is occurring. Here is a basic outline of my 6.0 c++ function:
  
  void functionname
  {
  // Initialize COM.
  HRESULT hr = CoInitialize(NULL);
  
  // Create the interface pointer.
  IManageInterfacePtr pIInterface(__uuidof(ManagerInterface));
  
  // Call the Add method.
  pIInterface->LaunchRSSDLL(string, string, string);
  
  pIInterface->Dispose(); <--this is from trying something with the C# dll
  
  pIInterface->Release();
  
  // Uninitialize COM.
  CoUninitialize();
  }
  
  I have put try/catch inside this function, around the call to this function, inside my C# DLL COM interface, and I still cannot find where the gpf is occurring. This is my first C# dll so be please be patient if I so kind of idiotic in describing this. Any ideas on what I may be missing? Any ideas on what I can look at?
  
  
  Report abuse
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  1 year ago

  by bla

  bla

  , United Kingdom

  Joined 3 years ago

  dahhhhhhhhhhhhhhhhhhhhhhh

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