不注册Activex 直接调用它

此处的Activex是ATL方式的。

[ComVisible(false)]
    [ComImport, InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("00000001-0000-0000-C000-000000000046")]
    internal interface IClassFactory
    {
        void CreateInstance([MarshalAs(UnmanagedType.Interface)] object pUnkOuter, ref Guid refiid, [MarshalAs(UnmanagedType.Interface)] out object ppunk);
        void LockServer(bool fLock);
    }
    public delegate void IETestKey(IntPtr values);

internal static class ComHelper
    {
        //DllGetClassObject fuction pointer signature
        private delegate int DllGetClassObject(ref Guid ClassId, ref Guid InterfaceId, [Out, MarshalAs(UnmanagedType.Interface)] out object ppunk);

//Some win32 methods to load\unload dlls and get a function pointer
        private class Win32NativeMethods
        {
            [DllImport("kernel32.dll", CharSet = CharSet.Ansi)]
            public static extern IntPtr GetProcAddress(IntPtr hModule, string lpProcName);

[DllImport("kernel32.dll")]
            public static extern bool FreeLibrary(IntPtr hModule);

[DllImport("kernel32.dll")]
            public static extern IntPtr LoadLibrary(string lpFileName);
        }

/// <summary>
        /// Holds a list of dll handles and unloads the dlls
        /// in the destructor
        /// </summary>
        private class DllList
        {
            private List<IntPtr> _dllList = new List<IntPtr>();
            public void AddDllHandle(IntPtr dllHandle)
            {
                lock (_dllList)
                {
                    _dllList.Add(dllHandle);
                }
            }

~DllList()
            {
                foreach (IntPtr dllHandle in _dllList)
                {
                    try
                    {
                        Win32NativeMethods.FreeLibrary(dllHandle);
                    }
                    catch { };
                }
            }
        }

static DllList _dllList = new DllList();

/// <summary>
        /// Gets a class factory for a specific COM Class ID.
        /// </summary>
        /// <param name="dllName">The dll where the COM class is implemented</param>
        /// <param name="filterPersistClass">The requested Class ID</param>
        /// <returns>IClassFactory instance used to create instances of that class</returns>
        internal static IClassFactory GetClassFactory(string dllName, string filterPersistClass)
        {
            //Load the class factory from the dll
            IClassFactory classFactory = GetClassFactoryFromDll(dllName, filterPersistClass);
            return classFactory;
        }

private static IClassFactory GetClassFactoryFromDll(string dllName, string filterPersistClass)
        {
            //Load the dll
            IntPtr dllHandle = Win32NativeMethods.LoadLibrary(dllName);
            if (dllHandle == IntPtr.Zero)
                return null;

//Keep a reference to the dll until the process\AppDomain dies
            _dllList.AddDllHandle(dllHandle);

//Get a pointer to the DllGetClassObject function
            IntPtr dllGetClassObjectPtr = Win32NativeMethods.GetProcAddress(dllHandle, "DllGetClassObject");
            if (dllGetClassObjectPtr == IntPtr.Zero)
                return null;

//Convert the function pointer to a .net delegate
            DllGetClassObject dllGetClassObject = (DllGetClassObject)Marshal.GetDelegateForFunctionPointer(dllGetClassObjectPtr, typeof(DllGetClassObject));

//Call the DllGetClassObject to retreive a class factory for out Filter class
            Guid filterPersistGUID = new Guid(filterPersistClass);
            //Guid IClassFactoryGUID = new Guid("FCF82F0F-F8A9-4527-A36E-CC87FAFAA270"); //IClassFactory class id
            Guid IClassFactoryGUID = new Guid("00000001-0000-0000-C000-000000000046"); //IClassFactory class id
            Object unk;
            if (dllGetClassObject(ref filterPersistGUID, ref IClassFactoryGUID, out unk) != 0)
                return null;

//Yippie! cast the returned object to IClassFactory
            return (unk as IClassFactory);
        }

public static Delegate TestDll(string dllName)
        {
            IntPtr dllHandle = Win32NativeMethods.LoadLibrary(dllName);
            if (dllHandle == IntPtr.Zero)
                return null;

//Keep a reference to the dll until the process\AppDomain dies
            //_dllList.AddDllHandle(dllHandle);

//Get a pointer to the DllGetClassObject function
            IntPtr dllGetClassObjectPtr = Win32NativeMethods.GetProcAddress(dllHandle, "DllGetClassObject");
            if (dllGetClassObjectPtr == IntPtr.Zero)
                return null;

return (Delegate)Marshal.GetDelegateForFunctionPointer(dllGetClassObjectPtr, typeof(IETestKey));
        }
    }

不说废话，上代码

public enum IFilterReturnCode : uint
    {
        /// <summary>
        /// Success
        /// </summary>
        S_OK = 0,
        /// <summary>
        /// The function was denied access to the filter file.
        /// </summary>
        E_ACCESSDENIED = 0x80070005,
        /// <summary>
        /// The function encountered an invalid handle,
        /// probably due to a low-memory situation.
        /// </summary>
        E_HANDLE = 0x80070006,
        /// <summary>
        /// The function received an invalid parameter.
        /// </summary>
        E_INVALIDARG = 0x80070057,
        /// <summary>
        /// Out of memory
        /// </summary>
        E_OUTOFMEMORY = 0x8007000E,
        /// <summary>
        /// Not implemented
        /// </summary>
        E_NOTIMPL = 0x80004001,
        /// <summary>
        /// Unknown error
        /// </summary>
        E_FAIL = 0x80000008,
        /// <summary>
        /// File not filtered due to password protection
        /// </summary>
        FILTER_E_PASSWORD = 0x8004170B,
        /// <summary>
        /// The document format is not recognised by the filter
        /// </summary>
        FILTER_E_UNKNOWNFORMAT = 0x8004170C,
        /// <summary>
        /// No text in current chunk
        /// </summary>
        FILTER_E_NO_TEXT = 0x80041705,
        /// <summary>
        /// No more chunks of text available in object
        /// </summary>
        FILTER_E_END_OF_CHUNKS = 0x80041700,
        /// <summary>
        /// No more text available in chunk
        /// </summary>
        FILTER_E_NO_MORE_TEXT = 0x80041701,
        /// <summary>
        /// No more property values available in chunk
        /// </summary>
        FILTER_E_NO_MORE_VALUES = 0x80041702,
        /// <summary>
        /// Unable to access object
        /// </summary>
        FILTER_E_ACCESS = 0x80041703,
        /// <summary>
        /// Moniker doesn't cover entire region
        /// </summary>
        FILTER_W_MONIKER_CLIPPED = 0x00041704,
        /// <summary>
        /// Unable to bind IFilter for embedded object
        /// </summary>
        FILTER_E_EMBEDDING_UNAVAILABLE = 0x80041707,
        /// <summary>
        /// Unable to bind IFilter for linked object
        /// </summary>
        FILTER_E_LINK_UNAVAILABLE = 0x80041708,
        /// <summary>
        ///  This is the last text in the current chunk
        /// </summary>
        FILTER_S_LAST_TEXT = 0x00041709,
        /// <summary>
        /// This is the last value in the current chunk
        /// </summary>
        FILTER_S_LAST_VALUES = 0x0004170A
    }

[ComImport, Guid("接口的GUID")]
    [InterfaceType(ComInterfaceType.InterfaceIsDual)]
    public interface ISISSKeyManager
    {      
        [DispId(1)]
        IFilterReturnCode IETestKey([Out, MarshalAs(UnmanagedType.BStr)] out string KeyInfo);
        [DispId(2)]
        IFilterReturnCode CheckKeys([In, MarshalAs(UnmanagedType.BStr)]string KeyInfo, [In, MarshalAs(UnmanagedType.BStr)]string KeyInfo2, [Out, MarshalAs(UnmanagedType.BStr)]out string KeyTest);
    }

public class LoadDllHelper
    {
       public static ISISSKeyManager LoadFilterFromDll(string dllName, string filterPersistClass)
       {
           //Get a classFactory for our classID
           IClassFactory classFactory = ComHelper.GetClassFactory(dllName, filterPersistClass);
           if (classFactory == null)
               return null;

//And create an IFilter instance using that class factory
           Guid IFilterGUID = new Guid("接口的GUID");
           Object obj;
           classFactory.CreateInstance(null, ref IFilterGUID, out obj);
           return (obj as ISISSKeyManager);
       }
    }

调用方式:

var gethelperId = LoadDllHelper.LoadFilterFromDll("xxxx.dll", "com的GUID");
                if (gethelperId != null)
                {
                    string str = "1".PadLeft(300, '1');
                    IntPtr outPtr = Marshal.StringToBSTR(str);
                    var s = gethelperId.IETestKey(out str);
                    MessageBox.Show(s.ToString());
                }