protected override Boolean RunDialog(IntPtr hwndOwner)
{
IntPtr pidlRoot = IntPtr.Zero;
Boolean result = false;
UnsafeNativeMethods.Shell32.SHGetSpecialFolderLocation(hwndOwner, (Int32)_rootFolder, ref pidlRoot);
if (pidlRoot == IntPtr.Zero)
{
UnsafeNativeMethods.Shell32.SHGetSpecialFolderLocation(hwndOwner, 0, ref pidlRoot);
if (pidlRoot == IntPtr.Zero)
{
throw new InvalidOperationException("Unable to retrieve the root folder.");
}
}
Int32 options = NEW_DIALOG_STYLE_OPTION;
if (!ShowNewFolderButton)
{
options += HIDE_NEW_FOLDER_BUTTON_OPTION;
}
IntPtr pidlRet = IntPtr.Zero;
IntPtr pszDisplayName = IntPtr.Zero;
IntPtr pszSelectedPath = IntPtr.Zero;
UnsafeNativeMethods.BrowseCallbackProc callback;
try
{
var browseInfo = new UnsafeNativeMethods.BrowseInfo();
pszDisplayName = Marshal.AllocHGlobal(MAX_PATH * Marshal.SystemDefaultCharSize);
pszSelectedPath = Marshal.AllocHGlobal(MAX_PATH * Marshal.SystemDefaultCharSize);
callback = new UnsafeNativeMethods.BrowseCallbackProc(BrowseCallbackHandler);
browseInfo.pidlRoot = pidlRoot;
browseInfo.hwndOwner = hwndOwner;
browseInfo.pszDisplayName = pszDisplayName;
browseInfo.lpszTitle = _descriptionText;
browseInfo.ulFlags = options;
browseInfo.lpfn = callback;
browseInfo.lParam = IntPtr.Zero;
browseInfo.iImage = 0;
pidlRet = UnsafeNativeMethods.Shell32.SHBrowseForFolder(browseInfo);
if (pidlRet != IntPtr.Zero)
{
UnsafeNativeMethods.Shell32.SHGetPathFromIDList(pidlRet, pszSelectedPath);
_selectedPathNeedsCheck = true;
_selectedPath = Marshal.PtrToStringAuto(pszSelectedPath);
result = true;
}
}
finally
{
UnsafeNativeMethods.Ole32.CoTaskMemFree(pidlRoot);
if (pidlRet != IntPtr.Zero)
{
UnsafeNativeMethods.Ole32.CoTaskMemFree(pidlRet);
}
if (pszSelectedPath != IntPtr.Zero)
{
Marshal.FreeHGlobal(pszSelectedPath);
}
if (pszDisplayName != IntPtr.Zero)
{
Marshal.FreeHGlobal(pszDisplayName);
}
callback = null;
}
return(result);
}
public static extern IntPtr SHBrowseForFolder([In] BrowseInfo lpbi);
