Path: blob/master/BizHawk.Client.EmuHawk/CustomControls/FolderBrowserDialogEx.cs
2 views
using System.Runtime.InteropServices;
using System.Text;
using System;
using System.Windows.Forms;
using System.ComponentModel;
using System.Security.Permissions;
//I believe this code is from http://support.microsoft.com/kb/306285
//The license is assumed to be effectively public domain.
//I saw a version of it with at least one bug fixed at https://github.com/slavat/MailSystem.NET/blob/master/Queuing%20System/ActiveQLibrary/CustomControl/FolderBrowser.cs
namespace BizHawk.Client.EmuHawk
{
/// <summary>
/// Component wrapping access to the Browse For Folder common dialog box.
/// Call the ShowDialog() method to bring the dialog box up.
/// </summary>
public sealed class FolderBrowserEx : Component
{
private const int MAX_PATH = 260;
// Root node of the tree view.
private FolderID startLocation = FolderID.Desktop;
// Browse info options.
private int publicOptions = (int) Win32API.Shell32.BffStyles.RestrictToFilesystem |
(int) Win32API.Shell32.BffStyles.RestrictToDomain;
private const int privateOptions = (int) (Win32API.Shell32.BffStyles.NewDialogStyle | Win32API.Shell32.BffStyles.ShowTextBox);
// Description text to show.
public string Description = "Please select a folder below:";
/// <summary>
/// Enum of CSIDLs identifying standard shell folders.
/// </summary>
public enum FolderID
{
Desktop = 0x0000,
Printers = 0x0004,
MyDocuments = 0x0005,
Favorites = 0x0006,
Recent = 0x0008,
SendTo = 0x0009,
StartMenu = 0x000b,
MyComputer = 0x0011,
NetworkNeighborhood = 0x0012,
Templates = 0x0015,
MyPictures = 0x0027,
NetAndDialUpConnections = 0x0031,
}
/// <summary>
/// Helper function that returns the IMalloc interface used by the shell.
/// </summary>
private static Win32API.IMalloc GetSHMalloc()
{
Win32API.IMalloc malloc;
Win32API.Shell32.SHGetMalloc(out malloc);
return malloc;
}
/// <summary>
/// Shows the folder browser dialog box.
/// </summary>
public DialogResult ShowDialog()
{
return ShowDialog(null);
}
private int callback(IntPtr hwnd, uint uMsg, IntPtr lParam, IntPtr lpData)
{
switch (uMsg)
{
case 1:
{
IntPtr str = Marshal.StringToHGlobalUni(SelectedPath);
Win32.SendMessage(hwnd, (0x400 + 103), 1, str.ToInt32());
Marshal.FreeHGlobal(str);
break;
}
}
return 0;
}
/// <summary>
/// Shows the folder browser dialog box with the specified owner window.
/// </summary>
public DialogResult ShowDialog(IWin32Window owner)
{
IntPtr pidlRoot = IntPtr.Zero;
// Get/find an owner HWND for this dialog.
IntPtr hWndOwner;
if (owner != null)
{
hWndOwner = owner.Handle;
}
else
{
hWndOwner = Win32API.GetActiveWindow();
}
// Get the IDL for the specific startLocation.
Win32API.Shell32.SHGetSpecialFolderLocation(hWndOwner, (int) startLocation, out pidlRoot);
if (pidlRoot == IntPtr.Zero)
{
return DialogResult.Cancel;
}
int mergedOptions = (int) publicOptions | (int) privateOptions;
if ((mergedOptions & (int) Win32API.Shell32.BffStyles.NewDialogStyle) != 0)
{
if (System.Threading.ApartmentState.MTA == Application.OleRequired())
mergedOptions = mergedOptions & (~(int) Win32API.Shell32.BffStyles.NewDialogStyle);
}
IntPtr pidlRet = IntPtr.Zero;
try
{
// Construct a BROWSEINFO.
Win32API.Shell32.BROWSEINFO bi = new Win32API.Shell32.BROWSEINFO();
IntPtr buffer = Marshal.AllocHGlobal(MAX_PATH);
bi.pidlRoot = pidlRoot;
bi.hwndOwner = hWndOwner;
bi.pszDisplayName = buffer;
bi.lpszTitle = Description;
bi.ulFlags = mergedOptions;
bi.lpfn = new Win32API.Shell32.BFFCALLBACK(callback);
// The rest of the fields are initialized to zero by the constructor.
// bi.lParam = IntPtr.Zero; bi.iImage = 0;
// Show the dialog.
pidlRet = Win32API.Shell32.SHBrowseForFolder(ref bi);
// Free the buffer you've allocated on the global heap.
Marshal.FreeHGlobal(buffer);
if (pidlRet == IntPtr.Zero)
{
// User clicked Cancel.
return DialogResult.Cancel;
}
// Then retrieve the path from the IDList.
StringBuilder sb = new StringBuilder(MAX_PATH);
if (0 == Win32API.Shell32.SHGetPathFromIDList(pidlRet, sb))
{
return DialogResult.Cancel;
}
// Convert to a string.
SelectedPath = sb.ToString();
}
finally
{
Win32API.IMalloc malloc = GetSHMalloc();
malloc.Free(pidlRoot);
if (pidlRet != IntPtr.Zero)
{
malloc.Free(pidlRet);
}
}
return DialogResult.OK;
}
/// <summary>
/// Helper function used to set and reset bits in the publicOptions bitfield.
/// </summary>
private void SetOptionField(int mask, bool turnOn)
{
if (turnOn)
publicOptions |= mask;
else
publicOptions &= ~mask;
}
/// <summary>
/// Only return file system directories. If the user selects folders
/// that are not part of the file system, the OK button is unavailable.
/// </summary>
[Category("Navigation")]
[Description("Only return file system directories. If the user selects folders " +
"that are not part of the file system, the OK button is unavailable.")]
[DefaultValue(true)]
public bool OnlyFilesystem
{
get { return (publicOptions & (int) Win32API.Shell32.BffStyles.RestrictToFilesystem) != 0; }
set { SetOptionField((int) Win32API.Shell32.BffStyles.RestrictToFilesystem, value); }
}
/// <summary>
/// Location of the root folder from which to start browsing. Only the specified
/// folder and any folders beneath it in the namespace hierarchy appear
/// in the dialog box.
/// </summary>
[Category("Navigation")]
[Description("Location of the root folder from which to start browsing. Only the specified " +
"folder and any folders beneath it in the namespace hierarchy appear " +
"in the dialog box.")]
[DefaultValue(typeof (FolderID), "0")]
public FolderID StartLocation
{
get { return startLocation; }
set
{
new UIPermission(UIPermissionWindow.AllWindows).Demand();
startLocation = value;
}
}
public string SelectedPath;
}
internal class Win32API
{
// C# representation of the IMalloc interface.
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown),
Guid("00000002-0000-0000-C000-000000000046")]
public interface IMalloc
{
[PreserveSig]
IntPtr Alloc([In] int cb);
[PreserveSig]
IntPtr Realloc([In] IntPtr pv, [In] int cb);
[PreserveSig]
void Free([In] IntPtr pv);
[PreserveSig]
int GetSize([In] IntPtr pv);
[PreserveSig]
int DidAlloc(IntPtr pv);
[PreserveSig]
void HeapMinimize();
}
[DllImport("User32.DLL")]
public static extern IntPtr GetActiveWindow();
public class Shell32
{
// Styles used in the BROWSEINFO.ulFlags field.
[Flags]
public enum BffStyles
{
RestrictToFilesystem = 0x0001, // BIF_RETURNONLYFSDIRS
RestrictToDomain = 0x0002, // BIF_DONTGOBELOWDOMAIN
RestrictToSubfolders = 0x0008, // BIF_RETURNFSANCESTORS
ShowTextBox = 0x0010, // BIF_EDITBOX
ValidateSelection = 0x0020, // BIF_VALIDATE
NewDialogStyle = 0x0040, // BIF_NEWDIALOGSTYLE
BrowseForComputer = 0x1000, // BIF_BROWSEFORCOMPUTER
BrowseForPrinter = 0x2000, // BIF_BROWSEFORPRINTER
BrowseForEverything = 0x4000, // BIF_BROWSEINCLUDEFILES
}
// Delegate type used in BROWSEINFO.lpfn field.
public delegate int BFFCALLBACK(IntPtr hwnd, uint uMsg, IntPtr lParam, IntPtr lpData);
[StructLayout(LayoutKind.Sequential, Pack = 8)]
public struct BROWSEINFO
{
public IntPtr hwndOwner;
public IntPtr pidlRoot;
public IntPtr pszDisplayName;
[MarshalAs(UnmanagedType.LPTStr)] public string lpszTitle;
public int ulFlags;
[MarshalAs(UnmanagedType.FunctionPtr)] public BFFCALLBACK lpfn;
public IntPtr lParam;
public int iImage;
}
[DllImport("Shell32.DLL")]
public static extern int SHGetMalloc(out IMalloc ppMalloc);
[DllImport("Shell32.DLL")]
public static extern int SHGetSpecialFolderLocation(
IntPtr hwndOwner, int nFolder, out IntPtr ppidl);
[DllImport("Shell32.DLL")]
public static extern int SHGetPathFromIDList(
IntPtr pidl, StringBuilder Path);
[DllImport("Shell32.DLL", CharSet = CharSet.Auto)]
public static extern IntPtr SHBrowseForFolder(ref BROWSEINFO bi);
}
}
}