Microsoft way to do folder browsing

http://support.microsoft.com/kb/306285

...

using System.Runtime.InteropServices;
using System.Text;
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 );
     }
  }
...
     
     

Very Complicated!!!