Added custom Folder Browser Dialog allowing the user to paste.

Author: odalet

WindowsPathEditor/FolderBrowserDialogEx.cs

@@ -0,0 +1,393 @@
+using System;
+using System.ComponentModel;
+using System.Runtime.InteropServices;
+using System.Security;
+using System.Security.Permissions;
+using System.Threading;
+using System.Windows.Forms;
+
+namespace WindowsPathEditor
+{
+    /// <summary>
+    /// Similar to <see cref="FolderBrowserDialog"/>, but provides a more
+    /// fine grained access to the creation flags of the dialog (<see cref="CreationFlags"/>
+    /// property).
+    /// </summary>
+    public sealed class FolderBrowserDialogEx : CommonDialog
+    {
+        /// <summary>
+        /// Various creation flags modifying the appearance 
+        /// and the behavior of the dialog.
+        /// </summary>
+        [Flags]
+        public enum Flags : int
+        {
+            /// <summary>
+            /// Only return file system directories. If the user selects 
+            /// folders that are not part of the file system, the OK button is grayed.
+            /// </summary>
+            /// <remarks>
+            /// The OK button remains enabled for "\\server" items, as well as 
+            /// "\\server\share" and directory items. However, if the user selects 
+            /// a "\\server" item, passing the PIDL returned by SHBrowseForFolder 
+            /// to SHGetPathFromIDList fails.
+            /// </remarks>
+            BIF_RETURNONLYFSDIRS = 0x0001,
+
+            /// <summary>
+            /// Do not include network folders below the domain level in 
+            /// the dialog box's tree view control.
+            /// </summary>
+            BIF_DONTGOBELOWDOMAIN = 0x0002,
+
+            /// <summary>
+            /// Include a status area in the dialog box. The callback function can set 
+            /// the status text by sending messages to the dialog box. This flag is not 
+            /// supported when BIF_NEWDIALOGSTYLE is specified.
+            /// </summary>
+            BIF_STATUSTEXT = 0x0004,
+
+            /// <summary>
+            /// Only return file system ancestors. An ancestor is a subfolder that 
+            /// is beneath the root folder in the namespace hierarchy. If the user 
+            /// selects an ancestor of the root folder that is not part of the file 
+            /// system, the OK button is grayed.
+            /// </summary>
+            BIF_RETURNANCESTORS = 0x0008,
+
+            /// <summary>
+            /// <b>Version 4.71.</b> Include an edit control in the browse dialog box 
+            /// that allows the user to type the name of an item.
+            /// </summary>
+            BIF_EDITBOX = 0x0010,
+
+            // TODO: continue filling documentation from MSDN...
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_VALIDATE = 0x0020,
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_NEWDIALOGSTYLE = 0x0040,
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_USENEWUI = 0x0050,
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_BROWSEINCLUDEURLS = 0x0080,
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_UAHINT = 0x0100,
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_NONEWFOLDERBUTTON = 0x0200,
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_NOTRANSLATETARGETS = 0x0400,
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_BROWSEFORCOMPUTER = 0x1000,
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_BROWSEFORPRINTER = 0x2000,
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_BROWSEINCLUDEFILES = 0x4000,
+
+            /// <summary>
+            /// 
+            /// </summary>
+            BIF_SHAREABLE = 0x8000
+        }
+
+        #region Interop
+
+        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
+        private class BROWSEINFO
+        {
+            public IntPtr hwndOwner;
+            public IntPtr pidlRoot;
+            public IntPtr pszDisplayName;
+            public string lpszTitle;
+            public int ulFlags;
+            public BrowseCallbackProc lpfn;
+            public IntPtr lParam;
+            public int iImage;
+        }
+
+        [ComImport, Guid("00000002-0000-0000-c000-000000000046"),
+        SuppressUnmanagedCodeSecurity,
+        InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
+        private interface IMalloc
+        {
+            [PreserveSig]
+            IntPtr Alloc(int cb);
+            [PreserveSig]
+            IntPtr Realloc(IntPtr pv, int cb);
+            [PreserveSig]
+            void Free(IntPtr pv);
+            [PreserveSig]
+            int GetSize(IntPtr pv);
+            [PreserveSig]
+            int DidAlloc(IntPtr pv);
+            [PreserveSig]
+            void HeapMinimize();
+        }
+
+        private const int BFFM_INITIALIZED = 1;
+        private const int BFFM_SELCHANGED = 2;
+        private const int BFFM_SETSELECTION = 0x466;
+        private const int BFFM_SETSELECTIONW = 0x467;
+        private const int BFFM_ENABLEOK = 0x465;
+
+        private delegate int BrowseCallbackProc(IntPtr hwnd, int msg, IntPtr lParam, IntPtr lpData);
+
+        [DllImport("user32.dll", CharSet = CharSet.Auto)]
+        private static extern IntPtr SendMessage(HandleRef hWnd, int msg, int wParam, string lParam);
+
+        [DllImport("user32.dll", CharSet = CharSet.Auto)]
+        private static extern IntPtr SendMessage(HandleRef hWnd, int msg, int wParam, int lParam);
+
+        [DllImport("shell32.dll", CharSet = CharSet.Auto)]
+        private static extern bool SHGetPathFromIDList(IntPtr pidl, IntPtr pszPath);
+
+        [DllImport("shell32.dll")]
+        private static extern int SHGetMalloc([Out, MarshalAs(UnmanagedType.LPArray)] IMalloc[] ppMalloc);
+
+        [DllImport("shell32.dll")]
+        private static extern int SHGetSpecialFolderLocation(IntPtr hwnd, int csidl, ref IntPtr ppidl);
+
+        [DllImport("shell32.dll", CharSet = CharSet.Auto)]
+        private static extern IntPtr SHBrowseForFolder([In] BROWSEINFO lpbi);
+
+        #endregion
+
+        private BrowseCallbackProc callback;
+        private string descriptionText;
+        private Environment.SpecialFolder rootFolder;
+        private string selectedPath;
+        private bool selectedPathNeedsCheck;
+
+        private Flags flags;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FolderBrowserDialogEx"/> class.
+        /// </summary>
+        public FolderBrowserDialogEx() : base() { Reset(); }
+
+        #region Properties
+
+        /// <summary>
+        /// Gets or sets the description.
+        /// </summary>
+        /// <value>The description.</value>
+        [Description("Folder Browser Dialog Description"),
+         Category("Folder browsing"), DefaultValue(""),
+         Browsable(true), Localizable(true)]
+        public string Description
+        {
+            get { return descriptionText; }
+            set { descriptionText = (value == null) ? string.Empty : value; }
+        }
+
+        /// <summary>
+        /// Gets or sets the root folder.
+        /// </summary>
+        /// <value>The root folder.</value>
+        [Description("Folder Browser Dialog Root Folder"), Localizable(false), DefaultValue(0),
+        Category("Folder Browsing"), Browsable(true)]
+        public Environment.SpecialFolder RootFolder
+        {
+            get { return rootFolder; }
+            set
+            {
+                if (!Enum.IsDefined(typeof(Environment.SpecialFolder), value))
+                    throw new InvalidEnumArgumentException("value",
+                        (int)value, typeof(Environment.SpecialFolder));
+                rootFolder = value;
+            }
+        }
+
+        /// <summary>
+        /// Gets or sets the selected path.
+        /// </summary>
+        /// <value>The selected path.</value>
+        [Description("Folder Browser Dialog Selected Path"), Category("Folder Browsing"),
+        Browsable(true), DefaultValue(""), Localizable(true)]
+        public string SelectedPath
+        {
+            get
+            {
+                if ((selectedPath != null) && (selectedPath.Length != 0) && selectedPathNeedsCheck)
+                    new FileIOPermission(FileIOPermissionAccess.PathDiscovery, selectedPath).Demand();
+                return selectedPath;
+            }
+            set
+            {
+                selectedPath = (value == null) ? string.Empty : value;
+                selectedPathNeedsCheck = false;
+            }
+        }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether to show the new folder button.
+        /// </summary>
+        /// <value>
+        /// 	<c>true</c> if the new folder button should be shown; otherwise, <c>false</c>.
+        /// </value>
+        [Category("Folder Browsing"), Localizable(false),
+         Description("Folder Browser Dialog Show New Folder Button"),
+         DefaultValue(true), Browsable(true)]
+        public bool ShowNewFolderButton
+        {
+            get
+            {
+                return ((flags & Flags.BIF_NONEWFOLDERBUTTON) !=
+                    Flags.BIF_NONEWFOLDERBUTTON);
+            }
+            set
+            {
+                if (value)
+                    flags &= ~Flags.BIF_NONEWFOLDERBUTTON;
+                else flags |= Flags.BIF_NONEWFOLDERBUTTON;
+            }
+        }
+
+        /// <summary>
+        /// Gets or sets the creation flags.
+        /// </summary>
+        /// <value>The creation flags.</value>
+        [Browsable(false), DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
+        public Flags CreationFlags
+        {
+            get { return flags; }
+            set { flags = value; }
+        }
+
+        #endregion
+
+        /// <summary>
+        /// Resets the properties of this common dialog box to their default values.
+        /// </summary>
+        public override void Reset()
+        {
+            rootFolder = Environment.SpecialFolder.Desktop;
+            descriptionText = string.Empty;
+            selectedPath = string.Empty;
+            selectedPathNeedsCheck = false;
+            flags = Flags.BIF_USENEWUI;
+        }
+
+        /// <summary>
+        /// When overridden in a derived class, specifies a common dialog box.
+        /// </summary>
+        /// <param name="hwndOwner">A value that represents the window handle of the owner window for the common dialog box.</param>
+        /// <returns>
+        /// true if the dialog box was successfully run; otherwise, false.
+        /// </returns>
+        protected override bool RunDialog(IntPtr hwndOwner)
+        {
+            IntPtr zero = IntPtr.Zero;
+            bool flag = false;
+            SHGetSpecialFolderLocation(hwndOwner, (int)rootFolder, ref zero);
+            if (zero == IntPtr.Zero)
+            {
+                SHGetSpecialFolderLocation(hwndOwner, 0, ref zero);
+                if (zero == IntPtr.Zero) throw new InvalidOperationException(
+                    "Folder Browser Dialog: no root folder");
+            }
+
+            //int flags = 0x40;
+            //if (!showNewFolderButton) flags += 0x200;
+
+            if (Control.CheckForIllegalCrossThreadCalls && (Application.OleRequired() != ApartmentState.STA))
+                throw new ThreadStateException("Debugging exception only: Thread must be STA");
+
+            IntPtr pidl = IntPtr.Zero;
+            IntPtr hglobal = IntPtr.Zero;
+            IntPtr pszPath = IntPtr.Zero;
+            try
+            {
+                BROWSEINFO lpbi = new BROWSEINFO();
+                hglobal = Marshal.AllocHGlobal((int)(260 * Marshal.SystemDefaultCharSize));
+                pszPath = Marshal.AllocHGlobal((int)(260 * Marshal.SystemDefaultCharSize));
+                callback = new BrowseCallbackProc(FolderBrowserDialog_BrowseCallbackProc);
+                lpbi.pidlRoot = zero;
+                lpbi.hwndOwner = hwndOwner;
+                lpbi.pszDisplayName = hglobal;
+                lpbi.lpszTitle = descriptionText;
+                lpbi.ulFlags = (int)flags;
+                lpbi.lpfn = callback;
+                lpbi.lParam = IntPtr.Zero;
+                lpbi.iImage = 0;
+                pidl = SHBrowseForFolder(lpbi);
+                if (pidl != IntPtr.Zero)
+                {
+                    SHGetPathFromIDList(pidl, pszPath);
+                    selectedPathNeedsCheck = true;
+                    selectedPath = Marshal.PtrToStringAuto(pszPath);
+                    flag = true;
+                }
+            }
+            finally
+            {
+                IMalloc sHMalloc = GetSHMalloc();
+                sHMalloc.Free(zero);
+                if (pidl != IntPtr.Zero) sHMalloc.Free(pidl);
+                if (pszPath != IntPtr.Zero) Marshal.FreeHGlobal(pszPath);
+                if (hglobal != IntPtr.Zero) Marshal.FreeHGlobal(hglobal);
+
+                callback = null;
+            }
+            return flag;
+        }
+
+        private static IMalloc GetSHMalloc()
+        {
+            IMalloc[] ppMalloc = new IMalloc[1];
+            SHGetMalloc(ppMalloc);
+            return ppMalloc[0];
+        }
+        private int FolderBrowserDialog_BrowseCallbackProc(IntPtr hwnd, int msg, IntPtr lParam, IntPtr lpData)
+        {
+            switch (msg)
+            {
+                case BFFM_INITIALIZED:
+                    if (selectedPath.Length != 0)
+                        SendMessage(new HandleRef(null, hwnd), BFFM_SETSELECTIONW, 1, selectedPath);
+                    break;
+
+                case BFFM_SELCHANGED:
+                    IntPtr pidl = lParam;
+                    if (pidl != IntPtr.Zero)
+                    {
+                        IntPtr pszPath = Marshal.AllocHGlobal((int)(260 * Marshal.SystemDefaultCharSize));
+                        bool flag = SHGetPathFromIDList(pidl, pszPath);
+                        Marshal.FreeHGlobal(pszPath);
+                        SendMessage(new HandleRef(null, hwnd), BFFM_ENABLEOK, 0, flag ? 1 : 0);
+                    }
+                    break;
+            }
+            return 0;
+        }
+    }
+}