/// <summary>
/// Retrieves the handle of the system image list.
/// </summary>
/// <exception cref="Exception">
/// The system image list handle has already been retrieved.
/// or
/// Unable to retrieve system image list handle.
/// </exception>
private static void InitImageList()
{
// Only initialize once.
if (m_bImgInit)
{
throw new Exception("The system image list handle has already been retrieved.");
}
// Retrieve the info for a fake file so we can get the image list handle.
SHFILEINFO shInfo = new SHFILEINFO();
SHGFI dwAttribs =
SHGFI.SHGFI_USEFILEATTRIBUTES |
SHGFI.SHGFI_SMALLICON |
SHGFI.SHGFI_SYSICONINDEX;
m_pImgHandle = NativeShellApi.SHGetFileInfo(".txt", NativeShellApi.FILE_ATTRIBUTE_NORMAL, out shInfo, (uint)Marshal.SizeOf(shInfo), dwAttribs);
// Make sure we got the handle.
if (m_pImgHandle.Equals(IntPtr.Zero))
{
throw new Exception("Unable to retrieve system image list handle.");
}
// Only allow one initialization.
m_bImgInit = true;
}
/// <summary>
/// Gets the system path for this shell item.
/// </summary>
/// <returns>A path string.</returns>
public string GetPath()
{
StringBuilder strBuffer = new StringBuilder(256);
NativeShellApi.SHGetPathFromIDList(
m_pIDL,
strBuffer
);
return(strBuffer.ToString());
}
/// <summary>
/// Constructor. Creates the ShellItem object for the Desktop.
/// </summary>
public ShellItem()
{
// new ShellItem() can only be called once.
if (m_bHaveRootShell)
{
throw new Exception("The Desktop shell item already exists so cannot be created again.");
}
// Obtain the root IShellFolder interface.
int hRes = NativeShellApi.SHGetDesktopFolder(ref m_shRootShell);
if (hRes != 0)
{
Marshal.ThrowExceptionForHR(hRes);
}
// Now get the PIDL for the Desktop shell item.
hRes = NativeShellApi.SHGetSpecialFolderLocation(IntPtr.Zero, CSIDL.CSIDL_DESKTOP, ref m_pIDL);
if (hRes != 0)
{
Marshal.ThrowExceptionForHR(hRes);
}
// Now retrieve some attributes for the root shell item.
SHFILEINFO shInfo = new SHFILEINFO();
NativeShellApi.SHGetFileInfo(m_pIDL, 0, out shInfo, (uint)Marshal.SizeOf(shInfo),
SHGFI.SHGFI_DISPLAYNAME |
SHGFI.SHGFI_PIDL |
SHGFI.SHGFI_SMALLICON |
SHGFI.SHGFI_SYSICONINDEX
);
// Set the arributes to object properties.
DisplayName = shInfo.szDisplayName;
IconIndex = shInfo.iIcon;
IsFolder = true;
HasSubFolder = true;
Path = GetPath();
// Internal with no set{} mutator.
m_shShellFolder = RootShellFolder;
m_bHaveRootShell = true;
}
/// <summary>
/// Constructor. Create a sub-item shell item object.
/// </summary>
/// <param name="shDesktop">IShellFolder interface of the Desktop</param>
/// <param name="pIDL">The fully qualified PIDL for this shell item</param>
/// <param name="shParent">The ShellItem object for this item's parent</param>
public ShellItem(IShellFolder shDesktop, IntPtr pIDL, ShellItem shParent)
{
// We need the Desktop shell item to exist first.
if (m_bHaveRootShell == false)
{
throw new Exception("The root shell item must be created before creating a sub-item");
}
// Create the FQ PIDL for this new item.
m_pIDL = NativeShellApi.ILCombine(shParent.PIDL, pIDL);
// Get the properties of this item.
SFGAOF uFlags = SFGAOF.SFGAO_FOLDER | SFGAOF.SFGAO_HASSUBFOLDER;
// Here we get some basic attributes.
shDesktop.GetAttributesOf(1, out m_pIDL, out uFlags);
IsFolder = Convert.ToBoolean(uFlags & SFGAOF.SFGAO_FOLDER);
HasSubFolder = Convert.ToBoolean(uFlags & SFGAOF.SFGAO_HASSUBFOLDER);
// Now we want to get extended attributes such as the icon index etc.
SHFILEINFO shInfo = new SHFILEINFO();
SHGFI vFlags =
SHGFI.SHGFI_SMALLICON |
SHGFI.SHGFI_SYSICONINDEX |
SHGFI.SHGFI_PIDL |
SHGFI.SHGFI_DISPLAYNAME;
NativeShellApi.SHGetFileInfo(m_pIDL, 0, out shInfo, (uint)Marshal.SizeOf(shInfo), vFlags);
DisplayName = shInfo.szDisplayName;
IconIndex = shInfo.iIcon;
Path = GetPath();
// Create the IShellFolder interface for this item.
if (IsFolder)
{
uint hRes = shParent.m_shShellFolder.BindToObject(pIDL, IntPtr.Zero, ref NativeShellApi.IID_IShellFolder, out m_shShellFolder);
if (hRes != 0)
{
Marshal.ThrowExceptionForHR((int)hRes);
}
}
}
