Autocomplete using ComWrappers

src/System.Windows.Forms.Primitives/src/Interop/Interop.CLSID.cs

@@ -1,11 +1,14 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
 internal partial class Interop
 {
     internal static class CLSID
     {
+        // 00BB2763-6A77-11D0-A535-00C04FD7D062
+        internal static Guid AutoComplete = new Guid(0x00BB2763, 0x6A77, 0x11D0, 0xA5, 0x35, 0x00, 0xC0, 0x4F, 0xD7, 0xD0, 0x62);
+
         // C0B4E2F3-BA21-4773-8DBA-335EC946EB8B
         internal static Guid FileSaveDialog = new Guid(0xC0B4E2F3, 0xBA21, 0x4773, 0x8D, 0xBA, 0x33, 0x5E, 0xC9, 0x46, 0xEB, 0x8B);
 

src/System.Windows.Forms.Primitives/src/Interop/Interop.IID.cs

@@ -9,6 +9,12 @@ internal static class IID
         // 618736E0-3C3D-11CF-810C-00AA00389B71
         public static Guid IAccessible = new Guid(0x618736E0, 0x3C3D, 0x11CF, 0x81, 0x0C, 0x00, 0xAA, 0x00, 0x38, 0x9B, 0x71);
 
+        // EAC04BC0-3791-11D2-BB95-0060977B464C
+        public static Guid IAutoComplete2 { get; } = new(0xEAC04BC0, 0x3791, 0x11D2, 0xBB, 0x95, 0x00, 0x60, 0x97, 0x7B, 0x46, 0x4C);
+
+        // 00000101-0000-0000-C000-000000000046
+        public static Guid IEnumString { get; } = new(0x00000101, 0x0000, 0x0000, 0xC0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x46);
+
         // E6FDD21A-163F-4975-9C8C-A69F1BA37034
         internal static Guid IFileDialogCustomize { get; } = new(0xE6FDD21A, 0x163F, 0x4975, 0x9C, 0x8C, 0xA6, 0x9F, 0x1B, 0xA3, 0x70, 0x34);
 

src/System.Windows.Forms.Primitives/src/Interop/WinFormsComWrappers.AutoCompleteWrapper.cs

@@ -0,0 +1,44 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.InteropServices;
+using System.Runtime.InteropServices.ComTypes;
+using System.Windows.Forms;
+
+internal partial class Interop
+{
+    internal unsafe partial class WinFormsComWrappers
+    {
+        internal class AutoCompleteWrapper
+        {
+            private IntPtr _wrappedInstance;
+
+            public AutoCompleteWrapper(IntPtr wrappedInstance)
+            {
+                _wrappedInstance = wrappedInstance.OrThrowIfZero();
+            }
+
+            internal IntPtr Instance => _wrappedInstance;
+
+            public void Dispose()
+            {
+                Marshal.Release(_wrappedInstance);
+                _wrappedInstance = IntPtr.Zero;
+            }
+
+            public HRESULT Init(IntPtr hwndEdit, IEnumString punkACL, IntPtr pwszRegKeyPath, IntPtr pwszQuickComplete)
+            {
+                var punkACLPtr = WinFormsComWrappers.Instance.GetOrCreateComInterfaceForObject(punkACL, CreateComInterfaceFlags.None);
+                return ((delegate* unmanaged<IntPtr, IntPtr, IntPtr, IntPtr, IntPtr, HRESULT>)(*(*(void***)_wrappedInstance + 3)))
+                        (_wrappedInstance, hwndEdit, punkACLPtr, pwszRegKeyPath, pwszQuickComplete);
+            }
+
+            public HRESULT SetOptions(Shell32.AUTOCOMPLETEOPTIONS dwFlag)
+            {
+                return ((delegate* unmanaged<IntPtr, Shell32.AUTOCOMPLETEOPTIONS, HRESULT>)(*(*(void***)_wrappedInstance + 5)))
+                    (_wrappedInstance, dwFlag);
+            }
+        }
+    }
+}

src/System.Windows.Forms.Primitives/src/Interop/WinFormsComWrappers.IEnumStringVtbl.cs

@@ -0,0 +1,84 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using System.Runtime.InteropServices.ComTypes;
+
+internal partial class Interop
+{
+    internal unsafe partial class WinFormsComWrappers
+    {
+        internal static class IEnumStringVtbl
+        {
+            public static IntPtr Create(IntPtr fpQueryInterface, IntPtr fpAddRef, IntPtr fpRelease)
+            {
+                IntPtr* vtblRaw = (IntPtr*)RuntimeHelpers.AllocateTypeAssociatedMemory(typeof(IEnumStringVtbl), IntPtr.Size * 7);
+                vtblRaw[0] = fpQueryInterface;
+                vtblRaw[1] = fpAddRef;
+                vtblRaw[2] = fpRelease;
+                vtblRaw[3] = (IntPtr)(delegate* unmanaged<IntPtr, int, IntPtr*, int*, int>)&Next;
+                vtblRaw[4] = (IntPtr)(delegate* unmanaged<IntPtr, int, int>)&Skip;
+                vtblRaw[5] = (IntPtr)(delegate* unmanaged<IntPtr, int>)&Reset;
+                vtblRaw[6] = (IntPtr)(delegate* unmanaged<IntPtr, IntPtr*, int>)&Clone;
+
+                return (IntPtr)vtblRaw;
+            }
+
+            [UnmanagedCallersOnly]
+            private static int Next(IntPtr thisPtr, int celt, IntPtr* rgelt, int* pceltFetched)
+            {
+                IEnumString inst = ComInterfaceDispatch.GetInstance<IEnumString>((ComInterfaceDispatch*)thisPtr);
+                string[] elt = new string[celt];
+                var result = inst.Next(celt, elt, (IntPtr)pceltFetched);
+                for (var i = 0; i < *pceltFetched; i++)
+                {
+                    rgelt[i] = Marshal.StringToCoTaskMemUni(elt[i]);
+                }
+
+                return result;
+            }
+
+            [UnmanagedCallersOnly]
+            private static int Skip(IntPtr thisPtr, int celt)
+            {
+                IEnumString inst = ComInterfaceDispatch.GetInstance<IEnumString>((ComInterfaceDispatch*)thisPtr);
+                return inst.Skip(celt);
+            }
+
+            [UnmanagedCallersOnly]
+            private static int Reset(IntPtr thisPtr)
+            {
+                try
+                {
+                    IEnumString inst = ComInterfaceDispatch.GetInstance<IEnumString>((ComInterfaceDispatch*)thisPtr);
+                    inst.Reset();
+                }
+                catch (Exception ex)
+                {
+                    return ex.HResult;
+                }
+
+                return S_OK;
+            }
+
+            [UnmanagedCallersOnly]
+            private static int Clone(IntPtr thisPtr, IntPtr* ppenum)
+            {
+                try
+                {
+                    IEnumString inst = ComInterfaceDispatch.GetInstance<IEnumString>((ComInterfaceDispatch*)thisPtr);
+                    inst.Clone(out var cloned);
+                    *ppenum = WinFormsComWrappers.Instance.GetOrCreateComInterfaceForObject(cloned, CreateComInterfaceFlags.None);
+                }
+                catch (Exception ex)
+                {
+                    return ex.HResult;
+                }
+
+                return S_OK;
+            }
+        }
+    }
+}

src/System.Windows.Forms.Primitives/src/Interop/WinFormsComWrappers.cs

@@ -6,6 +6,7 @@
 using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
+using System.Runtime.InteropServices.ComTypes;
 
 internal partial class Interop
 {
@@ -19,6 +20,7 @@ internal unsafe partial class WinFormsComWrappers : ComWrappers
         private const int S_OK = (int)Interop.HRESULT.S_OK;
         private static readonly ComInterfaceEntry* s_streamEntry = InitializeIStreamEntry();
         private static readonly ComInterfaceEntry* s_fileDialogEventsEntry = InitializeIFileDialogEventsEntry();
+        private static readonly ComInterfaceEntry* s_enumStringEntry = InitializeIEnumStringEntry();
 
         internal static WinFormsComWrappers Instance { get; } = new WinFormsComWrappers();
 
@@ -48,6 +50,18 @@ private WinFormsComWrappers() { }
             return wrapperEntry;
         }
 
+        private static ComInterfaceEntry* InitializeIEnumStringEntry()
+        {
+            GetIUnknownImpl(out IntPtr fpQueryInterface, out IntPtr fpAddRef, out IntPtr fpRelease);
+
+            IntPtr iEnumStringVtbl = IEnumStringVtbl.Create(fpQueryInterface, fpAddRef, fpRelease);
+
+            ComInterfaceEntry* wrapperEntry = (ComInterfaceEntry*)RuntimeHelpers.AllocateTypeAssociatedMemory(typeof(WinFormsComWrappers), sizeof(ComInterfaceEntry));
+            wrapperEntry->IID = IID.IEnumString;
+            wrapperEntry->Vtable = iEnumStringVtbl;
+            return wrapperEntry;
+        }
+
         protected override unsafe ComInterfaceEntry* ComputeVtables(object obj, CreateComInterfaceFlags flags, out int count)
         {
             if (obj is Interop.Ole32.IStream)
@@ -62,6 +76,12 @@ private WinFormsComWrappers() { }
                 return s_fileDialogEventsEntry;
             }
 
+            if (obj is IEnumString)
+            {
+                count = 1;
+                return s_enumStringEntry;
+            }
+
             throw new NotImplementedException($"ComWrappers for type {obj.GetType()} not implemented.");
         }
 
@@ -109,6 +129,14 @@ protected override object CreateObject(IntPtr externalComObject, CreateObjectFla
                 return new ShellItemArrayWrapper(shellItemArrayComObject);
             }
 
+            Guid autoCompleteIID = IID.IAutoComplete2;
+            hr = Marshal.QueryInterface(externalComObject, ref autoCompleteIID, out IntPtr autoCompleteComObject);
+            if (hr == S_OK)
+            {
+                Marshal.Release(externalComObject);
+                return new AutoCompleteWrapper(autoCompleteComObject);
+            }
+
             throw new NotImplementedException();
         }
 
@@ -143,6 +171,7 @@ private IntPtr GetOrCreateComInterfaceForObject(object obj)
             {
                 ShellItemWrapper siw => siw.Instance,
                 FileOpenDialogWrapper fodw => fodw.Instance,
+                FileSaveDialogWrapper fsdw => fsdw.Instance,
                 _ => GetOrCreateComInterfaceForObject(obj, CreateComInterfaceFlags.None),
             };
         }

src/System.Windows.Forms/src/System/Windows/Forms/StringSource.cs

@@ -2,16 +2,14 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-#nullable disable
-
 using System.Runtime.InteropServices;
 using System.Runtime.InteropServices.ComTypes;
 using static Interop;
 
 namespace System.Windows.Forms
 {
     /// <summary>
-    ///  Represents an internal class that is used bu ComboBox and TextBox AutoCompleteCustomSource property.
+    ///  Represents an internal class that is used by ComboBox and TextBox AutoCompleteCustomSource property.
     ///  This class is responsible for initializing the SHAutoComplete COM object and setting options in it.
     ///  The StringSource contains an array of Strings which is passed to the COM object as the custom source.
     /// </summary>
@@ -20,41 +18,30 @@ internal class StringSource : IEnumString
         private string[] strings;
         private int current;
         private int size;
-        private Shell32.IAutoComplete2 _autoCompleteObject2;
-
-        /// <summary>
-        ///  SHAutoComplete COM object CLSID.
-        /// </summary>
-        private static Guid autoCompleteClsid = new Guid("{00BB2763-6A77-11D0-A535-00C04FD7D062}");
+        private WinFormsComWrappers.AutoCompleteWrapper? _autoCompleteObject2;
 
         /// <summary>
         ///  Constructor.
         /// </summary>
         public StringSource(string[] strings)
         {
             Array.Clear(strings, 0, size);
-
-            if (strings is not null)
-            {
-                this.strings = strings;
-            }
+            this.strings = strings;
 
             current = 0;
-            size = (strings is null) ? 0 : strings.Length;
+            size = strings.Length;
 
-            Guid iid_iunknown = typeof(Shell32.IAutoComplete2).GUID;
-            HRESULT hr = Ole32.CoCreateInstance(
-                ref autoCompleteClsid,
+            var autoCompleteIID = IID.IAutoComplete2;
+            Ole32.CoCreateInstance(
+                in CLSID.AutoComplete,
                 IntPtr.Zero,
                 Ole32.CLSCTX.INPROC_SERVER,
-                ref iid_iunknown,
-                out object obj);
-            if (!hr.Succeeded())
-            {
-                throw Marshal.GetExceptionForHR((int)hr);
-            }
+                in autoCompleteIID,
+                out IntPtr autoComplete2Ptr).ThrowIfFailed();
 
-            _autoCompleteObject2 = (Shell32.IAutoComplete2)obj;
+            var obj = WinFormsComWrappers.Instance
+                .GetOrCreateObjectForComInstance(autoComplete2Ptr, CreateObjectFlags.None);
+            _autoCompleteObject2 = (WinFormsComWrappers.AutoCompleteWrapper)obj;
         }
 
         /// <summary>
@@ -73,7 +60,7 @@ public bool Bind(HandleRef edit, Shell32.AUTOCOMPLETEOPTIONS options)
                 return false;
             }
 
-            HRESULT hr = _autoCompleteObject2.Init(edit.Handle, (IEnumString)this, null, null);
+            HRESULT hr = _autoCompleteObject2.Init(edit.Handle, this, IntPtr.Zero, IntPtr.Zero);
             GC.KeepAlive(edit.Wrapper);
             return hr.Succeeded();
         }
@@ -82,22 +69,17 @@ public void ReleaseAutoComplete()
         {
             if (_autoCompleteObject2 is not null)
             {
-                Marshal.ReleaseComObject(_autoCompleteObject2);
+                _autoCompleteObject2.Dispose();
                 _autoCompleteObject2 = null;
             }
         }
 
         public void RefreshList(string[] newSource)
         {
             Array.Clear(strings, 0, size);
-
-            if (strings is not null)
-            {
-                strings = newSource;
-            }
-
+            strings = newSource;
             current = 0;
-            size = (strings is null) ? 0 : strings.Length;
+            size = strings.Length;
         }
 
         #region IEnumString Members