fixes #1537

since the `System.Runtime.InteropServices.ComTypes.IDataObject` of .net
core is missing the GUID, any OLE-Calls with this type will fail.

src/Windows/Avalonia.Win32/DataObject.cs

@@ -7,7 +7,6 @@ using System.Text;
 using Avalonia.Input;
 using Avalonia.Win32.Interop;
 using IDataObject = Avalonia.Input.IDataObject;
-using IOleDataObject = System.Runtime.InteropServices.ComTypes.IDataObject;
 using System.IO;
 using System.Runtime.Serialization.Formatters.Binary;
 

src/Windows/Avalonia.Win32/Interop/UnmanagedMethods.cs

@@ -974,7 +974,7 @@ namespace Avalonia.Win32.Interop
         public static extern int DragQueryFile(IntPtr hDrop, int iFile, StringBuilder lpszFile, int cch);
 
         [DllImport("ole32.dll", CharSet = CharSet.Auto, ExactSpelling = true, PreserveSig = false)]
-        public static extern void DoDragDrop(IDataObject dataObject, IDropSource dropSource, int allowedEffects, int[] finalEffect);
+        public static extern void DoDragDrop(IOleDataObject dataObject, IDropSource dropSource, int allowedEffects, int[] finalEffect);
 
 
 
@@ -1366,13 +1366,13 @@ namespace Avalonia.Win32.Interop
     internal interface IDropTarget
     {
         [PreserveSig]
-        UnmanagedMethods.HRESULT DragEnter([MarshalAs(UnmanagedType.Interface)] [In] IDataObject pDataObj, [MarshalAs(UnmanagedType.U4)] [In] int grfKeyState, [MarshalAs(UnmanagedType.U8)] [In] long pt, [In] [Out] ref DropEffect pdwEffect);
+        UnmanagedMethods.HRESULT DragEnter([MarshalAs(UnmanagedType.Interface)] [In] IOleDataObject pDataObj, [MarshalAs(UnmanagedType.U4)] [In] int grfKeyState, [MarshalAs(UnmanagedType.U8)] [In] long pt, [In] [Out] ref DropEffect pdwEffect);
         [PreserveSig]
         UnmanagedMethods.HRESULT DragOver([MarshalAs(UnmanagedType.U4)] [In] int grfKeyState, [MarshalAs(UnmanagedType.U8)] [In] long pt, [In] [Out] ref DropEffect pdwEffect);
         [PreserveSig]
         UnmanagedMethods.HRESULT DragLeave();
         [PreserveSig]
-        UnmanagedMethods.HRESULT Drop([MarshalAs(UnmanagedType.Interface)] [In] IDataObject pDataObj, [MarshalAs(UnmanagedType.U4)] [In] int grfKeyState, [MarshalAs(UnmanagedType.U8)] [In] long pt, [In] [Out] ref DropEffect pdwEffect);
+        UnmanagedMethods.HRESULT Drop([MarshalAs(UnmanagedType.Interface)] [In] IOleDataObject pDataObj, [MarshalAs(UnmanagedType.U4)] [In] int grfKeyState, [MarshalAs(UnmanagedType.U8)] [In] long pt, [In] [Out] ref DropEffect pdwEffect);
     }
 
     [ComImport]
@@ -1387,6 +1387,27 @@ namespace Avalonia.Win32.Interop
     }
 
 
+    [ComImport]
+    [Guid("0000010E-0000-0000-C000-000000000046")]
+    [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
+    public interface IOleDataObject
+    {
+        void GetData([In] ref FORMATETC format, out STGMEDIUM medium);
+        void GetDataHere([In] ref FORMATETC format, ref STGMEDIUM medium);
+        [PreserveSig]
+        int QueryGetData([In] ref FORMATETC format);
+        [PreserveSig]
+        int GetCanonicalFormatEtc([In] ref FORMATETC formatIn, out FORMATETC formatOut);
+        void SetData([In] ref FORMATETC formatIn, [In] ref STGMEDIUM medium, [MarshalAs(UnmanagedType.Bool)] bool release);
+        IEnumFORMATETC EnumFormatEtc(DATADIR direction);
+        [PreserveSig]
+        int DAdvise([In] ref FORMATETC pFormatetc, ADVF advf, IAdviseSink adviseSink, out int connection);
+        void DUnadvise(int connection);
+        [PreserveSig]
+        int EnumDAdvise(out IEnumSTATDATA enumAdvise);
+    }
+
+
     [StructLayoutAttribute(LayoutKind.Sequential)]
     internal struct _DROPFILES
     {

src/Windows/Avalonia.Win32/OleDataObject.cs

@@ -8,15 +8,14 @@ using System.Runtime.Serialization.Formatters.Binary;
 using System.Text;
 using Avalonia.Input;
 using Avalonia.Win32.Interop;
-using IDataObject = System.Runtime.InteropServices.ComTypes.IDataObject;
 
 namespace Avalonia.Win32
 {
     class OleDataObject : Avalonia.Input.IDataObject
     {
-        private IDataObject _wrapped;
+        private IOleDataObject _wrapped;
 
-        public OleDataObject(IDataObject wrapped)
+        public OleDataObject(IOleDataObject wrapped)
         {
             _wrapped = wrapped;
         }

src/Windows/Avalonia.Win32/OleDropTarget.cs

@@ -3,7 +3,6 @@ using Avalonia.Input.Raw;
 using Avalonia.Platform;
 using Avalonia.Win32.Interop;
 using IDataObject = Avalonia.Input.IDataObject;
-using IOleDataObject = System.Runtime.InteropServices.ComTypes.IDataObject;
 
 namespace Avalonia.Win32
 {