public int EnumObjects(IntPtr hwnd, ShellAPI.SHCONTF grfFlags, out IntPtr enumIDList)
{
checkDisposed();
return(_iShellFolder2.EnumObjects(hwnd, grfFlags, out enumIDList));
}
public void CanEnumerateDesktopFolders()
{
// Defines the type of items that we want to retieve below the desktop root item
const SHCONTF flags = SHCONTF.NONFOLDERS | SHCONTF.FOLDERS | SHCONTF.INCLUDEHIDDEN;
// Get the desktop root folder.
IntPtr ptrDesktopFolder = default(IntPtr);
IntPtr enumerator = default(IntPtr);
IShellFolder2 iDesktopFolder = null;
// Enumerate over children of given shell folder item using this interface
// https://msdn.microsoft.com/en-us/library/windows/desktop/bb761983(v=vs.85).aspx
IEnumIDList enumIDs = null;
try
{
HRESULT hr = NativeMethods.SHGetDesktopFolder(out ptrDesktopFolder);
Assert.IsTrue(hr == HRESULT.S_OK);
if (ptrDesktopFolder != IntPtr.Zero)
{
iDesktopFolder = (IShellFolder2)Marshal.GetTypedObjectForIUnknown(ptrDesktopFolder, typeof(IShellFolder2));
}
Assert.IsTrue(iDesktopFolder != null);
// Create an enumerator and enumerate over each item.
hr = iDesktopFolder.EnumObjects(IntPtr.Zero, flags, out enumerator);
Assert.IsTrue(hr == HRESULT.S_OK);
// Convert enum IntPtr to interface
enumIDs = (IEnumIDList)Marshal.GetTypedObjectForIUnknown(enumerator, typeof(IEnumIDList));
Assert.IsTrue(enumIDs != null);
uint fetched, count = 0;
IntPtr apidl = default(IntPtr);
// Get one item below desktop root at a time and process by getting its display name
for (; enumIDs.Next(1, out apidl, out fetched) == HRESULT.S_OK; count++)
{
if (fetched <= 0) // End this loop if no more items are available
{
break;
}
IntPtr ptrStr = default(IntPtr); // get strings for this item
try
{
string displayName = null, parseName = null;
ptrStr = Marshal.AllocCoTaskMem(NativeMethods.MAX_PATH * 2 + 4);
Marshal.WriteInt32(ptrStr, 0, 0);
StringBuilder buf = new StringBuilder(NativeMethods.MAX_PATH);
// The apidl ITEMIDLIST structures returned in the array are relative to
// the IShellFolder being enumerated.
if (iDesktopFolder.GetDisplayNameOf(apidl, SHGDNF.SHGDN_NORMAL, ptrStr) == HRESULT.S_OK)
{
NativeMethods.StrRetToBuf(ptrStr, ptrDesktopFolder, buf, NativeMethods.MAX_PATH);
displayName = buf.ToString();
}
if (iDesktopFolder.GetDisplayNameOf(apidl, SHGDNF.SHGDN_FORPARSING, ptrStr) == HRESULT.S_OK)
{
NativeMethods.StrRetToBuf(ptrStr, ptrDesktopFolder, buf, NativeMethods.MAX_PATH);
parseName = buf.ToString();
}
Assert.IsFalse(string.IsNullOrEmpty(displayName));
Assert.IsFalse(string.IsNullOrEmpty(parseName));
}
finally
{
ptrStr = PidlManager.FreeCoTaskMem(ptrStr);
apidl = PidlManager.FreeCoTaskMem(apidl);
}
}
// There should be more than one item below the desktop root item
// 'My PC', 'Recycle Bin', and 'Network' are already three
Assert.IsTrue(count > 2);
}
finally
{
if (enumerator != default(IntPtr))
{
Marshal.Release(enumerator);
}
if (iDesktopFolder != null)
{
Marshal.ReleaseComObject(iDesktopFolder);
}
if (ptrDesktopFolder != default(IntPtr))
{
Marshal.Release(ptrDesktopFolder);
}
}
}