[Registry Preview] Moving to a different API to call the File Picker (#25260)

* Moving from FileOpenPicker

Moving from FileOpenPicker to a Win32/PInvoke version, so it can be opened while running as Admin.

* Update Resources.resw

Replacing a lost string.

* Save file picker also crashed

Switched to Win32-based SafeFilePicker
Cleaned up some of the code which should now pass spell checking and removed pragmas

src/modules/registrypreview/RegistryPreviewUI/FileName.cs

@@ -0,0 +1,39 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Runtime.InteropServices;
+
+namespace RegistryPreview
+{
+    // Workaround for File Pickers that don't work while running as admin, per:
+    // https://github.com/microsoft/WindowsAppSDK/issues/2504
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
+    public struct FileName
+    {
+        public int StructSize;
+        public IntPtr HwndOwner;
+        public IntPtr Instance;
+        public string Filter;
+        public string CustomFilter;
+        public int MaxCustFilter;
+        public int FilterIndex;
+        public string File;
+        public int MaxFile;
+        public string FileTitle;
+        public int MaxFileTitle;
+        public string InitialDir;
+        public string Title;
+        public int Flags;
+        public short FileOffset;
+        public short FileExtension;
+        public string DefExt;
+        public IntPtr CustData;
+        public IntPtr Hook;
+        public string TemplateName;
+        public IntPtr PtrReserved;
+        public int Reserved;
+        public int FlagsEx;
+    }
+}

src/modules/registrypreview/RegistryPreviewUI/MainWindow.Events.cs

@@ -134,18 +134,18 @@ namespace RegistryPreview
                 }
             }
 
-            // Pull in a new REG file
-            FileOpenPicker fileOpenPicker = new FileOpenPicker();
-            fileOpenPicker.ViewMode = PickerViewMode.List;
-            fileOpenPicker.CommitButtonText = resourceLoader.GetString("OpenButtonText");
-            fileOpenPicker.SuggestedStartLocation = PickerLocationId.DocumentsLibrary;
-            fileOpenPicker.FileTypeFilter.Add(".reg");
+            // Pull in a new REG file - we have to use the direct Win32 method because FileOpenPicker crashes when it's
+            // called while running as admin
+            string filename = OpenFilePicker.ShowDialog(
+                resourceLoader.GetString("FilterRegistryName") + '\0' + "*.reg" + '\0' + resourceLoader.GetString("FilterAllFiles") + '\0' + "*.*" + '\0' + '\0',
+                resourceLoader.GetString("OpenDialogTitle"));
 
-            // Get the HWND so we an open the modal
-            IntPtr hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);
-            InitializeWithWindow.Initialize(fileOpenPicker, hWnd);
+            if (filename == string.Empty || File.Exists(filename) == false)
+            {
+                return;
+            }
 
-            StorageFile storageFile = await fileOpenPicker.PickSingleFileAsync();
+            StorageFile storageFile = await StorageFile.GetFileFromPathAsync(filename);
 
             if (storageFile != null)
             {
@@ -174,27 +174,23 @@ namespace RegistryPreview
         /// <summary>
         /// Uses a picker to save out a copy of the current reg file
         /// </summary>
-        private async void SaveAsButton_Click(object sender, RoutedEventArgs e)
+        private void SaveAsButton_Click(object sender, RoutedEventArgs e)
         {
-            // Save out a new REG file and then open it
-            FileSavePicker fileSavePicker = new FileSavePicker();
-            fileSavePicker.CommitButtonText = resourceLoader.GetString("SaveButtonText");
-            fileSavePicker.SuggestedStartLocation = PickerLocationId.DocumentsLibrary;
-            fileSavePicker.FileTypeChoices.Add("Registry file", new List<string>() { ".reg" });
-            fileSavePicker.SuggestedFileName = resourceLoader.GetString("SuggestFileName");
+            // Save out a new REG file and then open it - we have to use the direct Win32 method because FileOpenPicker crashes when it's
+            // called while running as admin
+            string filename = SaveFilePicker.ShowDialog(
+                resourceLoader.GetString("SuggestFileName"),
+                resourceLoader.GetString("FilterRegistryName") + '\0' + "*.reg" + '\0' + resourceLoader.GetString("FilterAllFiles") + '\0' + "*.*" + '\0' + '\0',
+                resourceLoader.GetString("SaveDialogTitle"));
 
-            // Get the HWND so we an save the modal
-            IntPtr hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);
-            InitializeWithWindow.Initialize(fileSavePicker, hWnd);
-
-            StorageFile storageFile = await fileSavePicker.PickSaveFileAsync();
-
-            if (storageFile != null)
+            if (filename == string.Empty)
             {
-                App.AppFilename = storageFile.Path;
-                SaveFile();
-                UpdateToolBarAndUI(OpenRegistryFile(App.AppFilename));
+                return;
             }
+
+            App.AppFilename = filename;
+            SaveFile();
+            UpdateToolBarAndUI(OpenRegistryFile(App.AppFilename));
         }
 
         /// <summary>

src/modules/registrypreview/RegistryPreviewUI/OpenFileName.cs

@@ -0,0 +1,36 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.InteropServices;
+
+namespace RegistryPreview
+{
+    // Workaround for File Pickers that don't work while running as admin, per:
+    // https://github.com/microsoft/WindowsAppSDK/issues/2504
+    public static partial class OpenFilePicker
+    {
+        [DllImport("comdlg32.dll", SetLastError = true, CharSet = CharSet.Auto)]
+        private static extern bool GetOpenFileName(ref FileName openFileName);
+
+        public static string ShowDialog(string filter, string dialogTitle)
+        {
+            FileName openFileName = default(FileName);
+            openFileName.StructSize = Marshal.SizeOf(openFileName);
+
+            openFileName.Filter = filter;
+            openFileName.File = new string(new char[256]);
+            openFileName.MaxFile = openFileName.File.Length;
+            openFileName.FileTitle = new string(new char[64]);
+            openFileName.MaxFileTitle = openFileName.FileTitle.Length;
+            openFileName.Title = dialogTitle;
+
+            if (GetOpenFileName(ref openFileName))
+            {
+                return openFileName.File;
+            }
+
+            return string.Empty;
+        }
+    }
+}

src/modules/registrypreview/RegistryPreviewUI/RegistryPreviewUI.csproj

@@ -24,6 +24,7 @@
 		<AssemblyDescription>PowerToys RegistryPreview</AssemblyDescription>
 		<RootNamespace>RegistryPreview</RootNamespace>
 		<DisableWinExeOutputInference>true</DisableWinExeOutputInference>
+		<AllowUnsafeBlocks>true</AllowUnsafeBlocks>
 	</PropertyGroup>
 
 	<!-- SelfContained=true requires RuntimeIdentifier to be set -->

src/modules/registrypreview/RegistryPreviewUI/SaveFileName.cs

@@ -0,0 +1,38 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.InteropServices;
+
+namespace RegistryPreview
+{
+    // Workaround for File Pickers that don't work while running as admin, per:
+    // https://github.com/microsoft/WindowsAppSDK/issues/2504
+    public static partial class SaveFilePicker
+    {
+        [DllImport("comdlg32.dll", SetLastError = true, CharSet = CharSet.Auto)]
+        private static extern bool GetSaveFileName(ref FileName saveFileName);
+
+        public static string ShowDialog(string suggestedFilename, string filter, string dialogTitle)
+        {
+            FileName saveFileName = default(FileName);
+            saveFileName.StructSize = Marshal.SizeOf(saveFileName);
+
+            saveFileName.Filter = filter;
+            saveFileName.File = new string(new char[256]);
+            saveFileName.MaxFile = saveFileName.File.Length;
+            saveFileName.File = string.Concat(suggestedFilename, saveFileName.File);
+            saveFileName.FileTitle = new string(new char[64]);
+            saveFileName.MaxFileTitle = saveFileName.FileTitle.Length;
+            saveFileName.Title = dialogTitle;
+            saveFileName.DefExt = "reg";
+
+            if (GetSaveFileName(ref saveFileName))
+            {
+                return saveFileName.File;
+            }
+
+            return string.Empty;
+        }
+    }
+}

src/modules/registrypreview/RegistryPreviewUI/Strings/en-US/Resources.resw

@@ -132,6 +132,12 @@
   <data name="FileSaveError" xml:space="preserve">
     <value>The REG file cannot be written to.</value>
   </data>
+  <data name="FilterAllFiles" xml:space="preserve">
+    <value>All files (*.*)</value>
+  </data>
+  <data name="FilterRegistryName" xml:space="preserve">
+    <value>Registry files (*.reg)</value>
+  </data>
   <data name="InvalidRegistryFile" xml:space="preserve">
     <value> doesn't appear to be a valid registry file!</value>
   </data>
@@ -153,8 +159,8 @@
   <data name="OpenButton.Label" xml:space="preserve">
     <value>Open file...</value>
   </data>
-  <data name="OpenButtonText" xml:space="preserve">
-    <value>Open</value>
+  <data name="OpenDialogTitle" xml:space="preserve">
+    <value>Open Registry file...</value>
   </data>
   <data name="RefreshButton.Label" xml:space="preserve">
     <value>Reload from file</value>