using System;
using System.Windows.Forms;
using System.ComponentModel;
using System.Security;
using System.Runtime.InteropServices;
using System.Text;
namespace FolderBrowser
{
public delegate bool ShowNewButtonHandler(string selectedPath);
/// Created By: Goldberg Royee
/// Date: 6/8/2006
/// Reason: This class is an extended class
/// for the folderBrowseDialog of .NET.
/// This class add a functionality to disable the 'Make New Folder' Button
/// whenever a CD path selected.
public class ExtendedFolderBrowser
{
#region Win32API Class
/// <summary>
///
/// </summary>
private class Win32API
{
[DllImport("shell32.dll", CharSet=CharSet.Auto)]
public static extern IntPtr SHBrowseForFolder([In] BROWSEINFO lpbi);
[DllImport("shell32.dll")]
public static extern int SHGetMalloc([Out, MarshalAs(UnmanagedType.LPArray)] IMalloc[] ppMalloc);
[DllImport("shell32.dll", CharSet=CharSet.Auto)]
public static extern bool SHGetPathFromIDList(IntPtr pidl, IntPtr pszPath);
[DllImport("shell32.dll")]
public static extern int SHGetSpecialFolderLocation(IntPtr hwnd, int csidl, ref IntPtr ppidl);
[DllImport("user32.dll", CharSet=CharSet.Auto)]
public static extern IntPtr SendMessage(HandleRef hWnd, int msg, int wParam, string lParam);
[DllImport("user32.dll", EntryPoint="SendMessage", CharSet=CharSet.Auto)]
public static extern IntPtr SendMessage2(HandleRef hWnd, int msg, int wParam, int lParam);
[DllImport("user32.dll")]
public static extern bool EnableWindow(IntPtr hWnd,bool bEnable);
[DllImport("user32.dll") ]
public static extern int GetWindowText(int hWnd, StringBuilder text, int count);
[DllImport("user32.dll") ]
public static extern IntPtr FindWindow(string lpClassName,string lpWindowName);
[DllImport("user32.dll")]
public static extern IntPtr GetWindowThreadProcessId(IntPtr hwnd, IntPtr lpdwProcessId);
[DllImport("user32.dll") ]
public static extern IntPtr FindWindowEx(IntPtr hwndParent,
IntPtr hwndChildAfter,
string lpszClass,
string lpszWindow
);
[StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto), ComVisible(false)]
public 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)]
public interface IMalloc
{
IntPtr Alloc(int cb);
void Free(IntPtr pv);
IntPtr Realloc(IntPtr pv, int cb);
int GetSize(IntPtr pv);
int DidAlloc(IntPtr pv);
void HeapMinimize();
}
public const int WM_LBUTTONDOWN = 0x0201;
public const int BFFM_INITIALIZED = 1;
public const int BFFM_SELCHANGED = 2;
public delegate int BrowseCallbackProc(IntPtr hwnd, int msg, IntPtr lParam, IntPtr lpData);
}
#endregion
#region InternalFolderBrowser Class
/// <summary>
///
/// </summary>
private class InternalFolderBrowser : CommonDialog
{
private string m_selectedPath = null;
private Environment.SpecialFolder m_rootFolder;
public event EventHandler SelectedFolderChanged;
private string m_descriptionText = String.Empty;
/// <summary>
///
/// </summary>
/// <returns></returns>
private Win32API.IMalloc GetSHMalloc()
{
Win32API.IMalloc[] mallocArray1 = new Win32API.IMalloc[1];
Win32API.SHGetMalloc(mallocArray1);
return mallocArray1[0];
}
/// <summary>
///
/// </summary>
public override void Reset()
{
m_rootFolder = Environment.SpecialFolder.Desktop;
m_selectedPath = string.Empty;
}
/// <summary>
///
/// </summary>
/// <param name="hwndOwner"></param>
/// <returns></returns>
protected override bool RunDialog(System.IntPtr hwndOwner)
{
IntPtr ptr1 = IntPtr.Zero;
bool flag1 = false;
Win32API.SHGetSpecialFolderLocation(hwndOwner, (int)m_rootFolder, ref ptr1);
if (ptr1 == IntPtr.Zero)
{
Win32API.SHGetSpecialFolderLocation(hwndOwner, 0, ref ptr1);
if (ptr1 == IntPtr.Zero)
{
throw new Exception("FolderBrowserDialogNoRootFolder");
}
}
//Initialize the OLE to current thread.
Application.OleRequired();
IntPtr ptr2 = IntPtr.Zero;
try
{
Win32API.BROWSEINFO browseinfo1 = new Win32API.BROWSEINFO();
IntPtr ptr3 = Marshal.AllocHGlobal((int) (260 * Marshal.SystemDefaultCharSize));
IntPtr ptr4 = Marshal.AllocHGlobal((int) (260 * Marshal.SystemDefaultCharSize));
Win32API.BrowseCallbackProc proc1 = new Win32API.BrowseCallbackProc(this.FolderBrowserDialog_BrowseCallbackProc);
browseinfo1.pidlRoot = ptr1;
browseinfo1.hwndOwner = hwndOwner;
browseinfo1.pszDisplayName = ptr3;
browseinfo1.lpszTitle = m_descriptionText;
browseinfo1.ulFlags = 0x40;
browseinfo1.lpfn = proc1;
browseinfo1.lParam = IntPtr.Zero;
browseinfo1.iImage = 0;
ptr2 = Win32API.SHBrowseForFolder(browseinfo1);
string s = Marshal.PtrToStringAuto(ptr3);
if (ptr2 != IntPtr.Zero)
{
Win32API.SHGetPathFromIDList(ptr2, ptr4);
this.m_selectedPath = Marshal.PtrToStringAuto(ptr4);
Marshal.FreeHGlobal(ptr4);
Marshal.FreeHGlobal(ptr3);
flag1 = true;
}
}
finally
{
Win32API.IMalloc malloc1 = GetSHMalloc();
malloc1.Free(ptr1);
if (ptr2 != IntPtr.Zero)
{
malloc1.Free(ptr2);
}
}
return flag1;
}
/// <summary>
///
/// </summary>
/// <param name="hwnd"></param>
/// <param name="msg"></param>
/// <param name="lParam"></param>
/// <param name="lpData"></param>
/// <returns></returns>
private int FolderBrowserDialog_BrowseCallbackProc(IntPtr hwnd, int msg, IntPtr lParam, IntPtr lpData)
{
switch (msg)
{
case Win32API.BFFM_INITIALIZED:
if (m_selectedPath != string.Empty)
{
Win32API.SendMessage(new HandleRef(null, hwnd), 0x467, 1, m_selectedPath);
}
break;
case Win32API.BFFM_SELCHANGED: //Selction Changed
{
IntPtr ptr1 = lParam;
if (ptr1 != IntPtr.Zero)
{
IntPtr ptr2 = Marshal.AllocHGlobal((int) (260 * Marshal.SystemDefaultCharSize));
bool flag1 = Win32API.SHGetPathFromIDList(ptr1, ptr2);
m_selectedPath = Marshal.PtrToStringAuto(ptr2);
//Fire Event
if(SelectedFolderChanged != null)
{
SelectedFolderChanged(this,null);
}
Marshal.FreeHGlobal(ptr2);
Win32API.SendMessage2(new HandleRef(null, hwnd), 0x465, 0, flag1 ? 1 : 0);
}
break;
}
}
return 0;
}
/// <summary>
///
/// </summary>
public string SelectedPath
{
get
{
return m_selectedPath;
}
}
/// <summary>
///
/// </summary>
public string Description
{
get
{
return m_descriptionText;
}
set
{
m_descriptionText = (value == null) ? string.Empty : value;
}
}
}
#endregion
#region Private Members
private InternalFolderBrowser m_InternalFolderBrowser = null;
public event EventHandler SelectedFolderChanged;
private const string MAKE_NEW_FOLDER_BUTTON = "&Make New Folder";
private ShowNewButtonHandler m_ShowNewButtonHandler = null;
private const string BROWSE_FOR_FOLDER_CLASS_NAME = "#32770";
#endregion
#region CTOR
/// <summary>
///
/// </summary>
public ExtendedFolderBrowser()
{
m_InternalFolderBrowser = new InternalFolderBrowser();
m_InternalFolderBrowser.SelectedFolderChanged+=new EventHandler(m_InternalFolderBrowser_SelectedFolderChanged);
}
#endregion
#region Helper Methods
/// <summary>
///
/// </summary>
/// <param name="handle"></param>
/// <param name="state"></param>
private void UpdateButtonState(IntPtr handle, bool state)
{
if(handle != IntPtr.Zero)
{
Win32API.EnableWindow(handle,state);
}
}
/// <summary>
///
/// </summary>
/// <param name="windowHandle"></param>
/// <returns></returns>
private bool isFromTheSameThread(IntPtr windowHandle)
{
//Get the thread that running given handler
IntPtr activeThreadID = Win32API.GetWindowThreadProcessId(windowHandle,
IntPtr.Zero);
//Get current thread
int currentThread = AppDomain.GetCurrentThreadId();
return (currentThread == activeThreadID.ToInt32());
}
private IntPtr GetButtonHandle(IntPtr handle)
{
//First time
if(handle == IntPtr.Zero)
{
//Get Handle for class with name "#32770"
IntPtr parent = Win32API.FindWindow(BROWSE_FOR_FOLDER_CLASS_NAME,null);
//If the window we found is in the same thread we are running
//then it is The 'Browse For Folder' Dialog, otherwise keep searching
if(!isFromTheSameThread(parent))
{
//Keep searching from this point
return GetButtonHandle(parent);
}
else
{
return Win32API.FindWindowEx(parent,IntPtr.Zero,"Button", null);
}
}
else
{
//Find next window
IntPtr parent = Win32API.FindWindowEx(IntPtr.Zero,handle,BROWSE_FOR_FOLDER_CLASS_NAME, null);
if(!isFromTheSameThread(parent))
{
return GetButtonHandle(parent);
}
else
{
//We found the 'Browse For Folder' Dialog handler.
//Lets return the child handler of 'Maker new Folder' button
return Win32API.FindWindowEx(parent,IntPtr.Zero,"Button", null);
}
}
}
/// <summary>
/// A different version for finding the 'Make New Foler' button handler.
/// We currently don't use this version, because it requires a Localization.
/// </summary>
/// <returns></returns>
private IntPtr GetButtonHandle()
{
//This should be using localization!!!!!!!!!!!!!!!!!#32770 (Dialog)
IntPtr root = Win32API.FindWindow(null,"Browse For Folder");
IntPtr child = Win32API.FindWindowEx(root,IntPtr.Zero,"Button", null);
return child;
}
/// <summary>
/// Check if we should disable the 'Make New Folder' button
/// </summary>
private void CheckState()
{
if(m_ShowNewButtonHandler != null)
{
if(m_ShowNewButtonHandler(SelectedPath))
{
//Disabel the button
UpdateButtonState(GetButtonHandle(IntPtr.Zero), false);
}
else
{
//Enable the button
UpdateButtonState(GetButtonHandle(IntPtr.Zero),true);
}
}
}
private void m_InternalFolderBrowser_SelectedFolderChanged(object sender, EventArgs e)
{
CheckState();
//Fire event selection has changed in case anyone wants
//to be notified.
if(SelectedFolderChanged != null)
{
SelectedFolderChanged(sender,e);
}
}
#endregion
#region FolderBrowserDialog Mathods
public DialogResult ShowDialog()
{
return ShowDialog(null);
}
public DialogResult ShowDialog(IWin32Window owner)
{
return m_InternalFolderBrowser.ShowDialog(owner);
}
public string SelectedPath
{
get
{
return m_InternalFolderBrowser.SelectedPath;
}
}
public string Description
{
get
{
return m_InternalFolderBrowser.Description;
}
set
{
m_InternalFolderBrowser.Description = value;
}
}
/// <summary>
/// Pass the delegate to your function, which will decide
/// if to enable the 'Make New Folder' button or not.
/// </summary>
public ShowNewButtonHandler SetNewFolderButtonCondition
{
get
{
return m_ShowNewButtonHandler;;
}
set
{
m_ShowNewButtonHandler = value;
}
}
#endregion
}
}
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