public class ComHelper { /// <summary> /// Returns a string value representing the type name of the specified COM object. /// </summary> /// <param name="comObj">A COM object the type name of which to return.</param> /// <returns>A string containing the type name.</returns> public static string GetTypeName(object comObj) { if (comObj == null) return String.Empty; if (!Marshal.IsComObject(comObj)) //The specified object is not a COM object return String.Empty; IDispatch dispatch = comObj as IDispatch; if (dispatch == null) //The specified COM object doesn't support getting type information return String.Empty; System.Runtime.InteropServices.ComTypes.ITypeInfo typeInfo = null; try { try { // obtain the ITypeInfo interface from the object dispatch.GetTypeInfo(0, 0, out typeInfo); } catch (Exception ex) { #if LINQPAD ex.Dump(); #endif //Cannot get the ITypeInfo interface for the specified COM object return String.Empty; } string typeName = ""; string documentation, helpFile; int helpContext = -1; try { //retrieves the documentation string for the specified type description typeInfo.GetDocumentation(-1, out typeName, out documentation, out helpContext, out helpFile); } catch (Exception ex) { // Cannot extract ITypeInfo information return String.Empty; } return typeName; } catch (Exception ex) { // Unexpected error return String.Empty; } finally { if (typeInfo != null) Marshal.ReleaseComObject(typeInfo); } } } /// <summary> /// Exposes objects, methods and properties to programming tools and other /// applications that support Automation. /// </summary> [ComImport()] [Guid("00020400-0000-0000-C000-000000000046")] [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)] interface IDispatch { [PreserveSig] int GetTypeInfoCount(out int Count); [PreserveSig] int GetTypeInfo( [MarshalAs(UnmanagedType.U4)] int iTInfo, [MarshalAs(UnmanagedType.U4)] int lcid, out System.Runtime.InteropServices.ComTypes.ITypeInfo typeInfo); [PreserveSig] int GetIDsOfNames( ref Guid riid, [MarshalAs(UnmanagedType.LPArray, ArraySubType = UnmanagedType.LPWStr)] string[] rgsNames, int cNames, int lcid, [MarshalAs(UnmanagedType.LPArray)] int[] rgDispId); [PreserveSig] int Invoke( int dispIdMember, ref Guid riid, uint lcid, ushort wFlags, ref System.Runtime.InteropServices.ComTypes.DISPPARAMS pDispParams, out object pVarResult, ref System.Runtime.InteropServices.ComTypes.EXCEPINFO pExcepInfo, IntPtr[] pArgErr); }
When Abstractions Break
5 weeks ago