Merge pull request #62 from lozo2010/master

Add support for multiselect folder browser

Author: augustoproiete

sample/Ookii.Dialogs.Wpf.Sample/MainWindow.xaml

@@ -16,6 +16,7 @@
                 <ComboBoxItem>Progress Dialog</ComboBoxItem>
                 <ComboBoxItem>Credential Dialog</ComboBoxItem>
                 <ComboBoxItem>Vista-style Folder Browser Dialog</ComboBoxItem>
+                <ComboBoxItem>Vista-style Folder Browser Dialog (Select Multiple)</ComboBoxItem>
                 <ComboBoxItem>Vista-style Open File Dialog</ComboBoxItem>
                 <ComboBoxItem>Vista-style Save File Dialog</ComboBoxItem>
             </ComboBox.Items>

sample/Ookii.Dialogs.Wpf.Sample/MainWindow.xaml.cs

@@ -60,9 +60,12 @@ private void _showDialogButton_Click(object sender, RoutedEventArgs e)
                 ShowFolderBrowserDialog();
                 break;
             case 5:
-                ShowOpenFileDialog();
+                ShowFolderBrowserDialogSelectMultiple();
                 break;
             case 6:
+                ShowOpenFileDialog();
+                break;
+            case 7:
                 ShowSaveFileDialog();
                 break;
             }
@@ -162,13 +165,46 @@ private void ShowCredentialDialog()
 
         private void ShowFolderBrowserDialog()
         {
-            VistaFolderBrowserDialog dialog = new VistaFolderBrowserDialog();
+            var dialog = new VistaFolderBrowserDialog();
             dialog.Description = "Please select a folder.";
             dialog.UseDescriptionForTitle = true; // This applies to the Vista style dialog only, not the old dialog.
-            if( !VistaFolderBrowserDialog.IsVistaFolderDialogSupported )
+
+            if (!VistaFolderBrowserDialog.IsVistaFolderDialogSupported)
+            {
                 MessageBox.Show(this, "Because you are not using Windows Vista or later, the regular folder browser dialog will be used. Please use Windows Vista to see the new dialog.", "Sample folder browser dialog");
-            if( (bool)dialog.ShowDialog(this) )
-                MessageBox.Show(this, "The selected folder was: " + dialog.SelectedPath, "Sample folder browser dialog");            
+            }
+
+            if ((bool)dialog.ShowDialog(this))
+            {
+                MessageBox.Show(this, $"The selected folder was:{Environment.NewLine}{dialog.SelectedPath}", "Sample folder browser dialog");
+            }
+        }
+
+        private void ShowFolderBrowserDialogSelectMultiple()
+        {
+            var dialog = new VistaFolderBrowserDialog();
+            dialog.Multiselect = true;
+            dialog.Description = "Please select a folder.";
+            dialog.UseDescriptionForTitle = true; // This applies to the Vista style dialog only, not the old dialog.
+
+            if (!VistaFolderBrowserDialog.IsVistaFolderDialogSupported)
+            {
+                MessageBox.Show(this, "Because you are not using Windows Vista or later, the regular folder browser dialog will be used. Please use Windows Vista to see the new dialog.", "Sample folder browser dialog");
+            }
+
+            if ((bool)dialog.ShowDialog(this))
+            {
+                var selectedPaths = dialog.SelectedPaths;
+
+                if (selectedPaths.Length == 1)
+                {
+                    MessageBox.Show(this, $"The selected folder was:{Environment.NewLine}{selectedPaths[0]}", "Sample folder browser dialog");
+                }
+                else
+                {
+                    MessageBox.Show(this, $"The selected folders were:{Environment.NewLine}{string.Join(Environment.NewLine, selectedPaths)}", "Sample folder browser dialog");
+                }
+            }
         }
 
         private void ShowOpenFileDialog()

src/Ookii.Dialogs.Wpf/VistaFolderBrowserDialog.cs

@@ -23,6 +23,7 @@
 using System.Windows.Interop;
 using System.Windows;
 using System.Runtime.InteropServices;
+using System.Linq;
 
 namespace Ookii.Dialogs.Wpf
 {
@@ -40,6 +41,8 @@ public sealed class VistaFolderBrowserDialog
     {
         private string _description;
         private string _selectedPath;
+        private NativeMethods.FOS _options;
+        private string[] _selectedPaths;
 
         /// <summary>
         /// Creates a new instance of the <see cref="VistaFolderBrowserDialog" /> class.
@@ -108,8 +111,14 @@ public string SelectedPath
         {
             get
             {
-                return _selectedPath ?? string.Empty;
+                var selectedPath =
+                    _selectedPath ??
+                    _selectedPaths?.FirstOrDefault() ??
+                    string.Empty;
+
+                return selectedPath;
             }
+
             set
             {
                 _selectedPath = value;
@@ -135,6 +144,63 @@ public string SelectedPath
         [Category("Folder Browsing"), DefaultValue(false), Description("A value that indicates whether to use the value of the Description property as the dialog title for Vista style dialogs. This property has no effect on old style dialogs.")]
         public bool UseDescriptionForTitle { get; set; }
 
+        /// <summary>
+        /// Gets or sets a value indicating whether the dialog box allows multiple folder to be selected.
+        /// </summary>
+        /// <value>
+        /// <see langword="true" /> if the dialog box allows multiple folder to be selected together or concurrently; otherwise, <see langword="false" />. 
+        /// The default value is <see langword="false" />.
+        /// </value>
+        [Description("A value indicating whether the dialog box allows multiple folders to be selected."), DefaultValue(false), Category("Behavior")]
+        public bool Multiselect
+        {
+            get
+            {
+                return HasOption(NativeMethods.FOS.FOS_ALLOWMULTISELECT);
+            }
+
+            set
+            {
+                SetOption(NativeMethods.FOS.FOS_ALLOWMULTISELECT, value);
+            }
+        }
+
+        /// <summary>
+        /// Gets the folder paths of all selected folder in the dialog box.
+        /// </summary>
+        /// <value>
+        /// An array of type <see cref="string"/>, containing the folder paths of all selected folder in the dialog box.
+        /// </value>
+        [Description("The folder path of all selected folder in the dialog box."), Browsable(false), DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
+        public string[] SelectedPaths
+        {
+            get
+            {
+                var selectedPaths = _selectedPaths;
+
+                if (selectedPaths is null)
+                {
+                    var selectedPath = _selectedPath;
+                    if (string.IsNullOrWhiteSpace(selectedPath))
+                    {
+                        return new string[0];
+                    }
+                    else
+                    {
+                        return new[] { selectedPath };
+                    }
+                }
+
+                return (string[])selectedPaths.Clone();
+            }
+
+            set
+            {
+                _selectedPaths = value;
+            }
+        }
+
+
         #endregion
 
         #region Public Methods
@@ -149,6 +215,8 @@ public void Reset()
             _selectedPath = string.Empty;
             RootFolder = Environment.SpecialFolder.Desktop;
             ShowNewFolderButton = true;
+            _selectedPaths = null;
+            _options = 0;
         }
 
         /// <summary>
@@ -184,6 +252,27 @@ public void Reset()
 
         #endregion
 
+        #region Internal Methods
+
+        internal void SetOption(NativeMethods.FOS option, bool value)
+        {
+            if (value)
+            {
+                _options |= option;
+            }
+            else
+            {
+                _options &= ~option;
+            }
+        }
+
+        internal bool HasOption(NativeMethods.FOS option)
+        {
+            return (_options & option) != 0;
+        }
+
+        #endregion
+
         #region Private Methods
 
         private bool RunDialog(IntPtr owner)
@@ -275,9 +364,9 @@ private void SetDialogProperties(Ookii.Dialogs.Wpf.Interop.IFileDialog dialog)
                 }
             }
 
-            dialog.SetOptions(NativeMethods.FOS.FOS_PICKFOLDERS | NativeMethods.FOS.FOS_FORCEFILESYSTEM | NativeMethods.FOS.FOS_FILEMUSTEXIST);
+            dialog.SetOptions(NativeMethods.FOS.FOS_PICKFOLDERS | NativeMethods.FOS.FOS_FORCEFILESYSTEM | NativeMethods.FOS.FOS_FILEMUSTEXIST | _options);
 
-            if( !string.IsNullOrEmpty(_selectedPath) )
+            if ( !string.IsNullOrEmpty(_selectedPath) )
             {
                 string parent = Path.GetDirectoryName(_selectedPath);
                 if( parent == null || !Directory.Exists(parent) )
@@ -293,11 +382,30 @@ private void SetDialogProperties(Ookii.Dialogs.Wpf.Interop.IFileDialog dialog)
             }
         }
 
-        private void GetResult(Ookii.Dialogs.Wpf.Interop.IFileDialog dialog)
+        private void GetResult(IFileDialog dialog)
         {
-            Ookii.Dialogs.Wpf.Interop.IShellItem item;
-            dialog.GetResult(out item);
-            item.GetDisplayName(NativeMethods.SIGDN.SIGDN_FILESYSPATH, out _selectedPath);
+            if (Multiselect)
+            {
+                ((IFileOpenDialog)dialog).GetResults(out IShellItemArray results);
+
+                results.GetCount(out uint count);
+                string[] folderPaths = new string[count];
+
+                for (uint x = 0; x < count; ++x)
+                {
+                    results.GetItemAt(x, out IShellItem item);
+                    item.GetDisplayName(NativeMethods.SIGDN.SIGDN_FILESYSPATH, out string name);
+
+                    folderPaths[x] = name;
+                }
+
+                SelectedPaths = folderPaths;
+            }
+            else
+            {
+                dialog.GetResult(out IShellItem item);
+                item.GetDisplayName(NativeMethods.SIGDN.SIGDN_FILESYSPATH, out _selectedPath);
+            }
         }
 
         private int BrowseCallbackProc(IntPtr hwnd, NativeMethods.FolderBrowserDialogMessage msg, IntPtr lParam, IntPtr wParam)