/// <summary>
/// Returns the index of the icon for the specified file
/// </summary>
/// <param name="fileName">FileName to get icon for</param>
/// <param name="forceLoadFromDisk">If True, then hit the disk to get the icon,
/// otherwise only hit the disk if no cached icon is available.</param>
/// <param name="iconState">Flags specifying the state of the icon
/// returned.</param>
/// <returns>Index of the icon</returns>
public int IconIndex(string fileName,bool forceLoadFromDisk,ShellIconStateConstants iconState)
{
SHGetFileInfoConstants dwFlags = SHGetFileInfoConstants.SHGFI_SYSICONINDEX;
int dwAttr = 0;
if (size == ShellImageListSize.SmallIcons)
{
dwFlags |= SHGetFileInfoConstants.SHGFI_SMALLICON;
}
// We can choose whether to access the disk or not. If you don't
// hit the disk, you may get the wrong icon if the icon is
// not cached. Also only works for files.
if (!forceLoadFromDisk)
{
dwFlags |= SHGetFileInfoConstants.SHGFI_USEFILEATTRIBUTES;
dwAttr = FILE_ATTRIBUTE_NORMAL;
}
else
{
dwAttr = 0;
}
// sFileSpec can be any file. You can specify a
// file that does not exist and still get the
// icon, for example sFileSpec = "C:\PANTS.DOC"
var shfi = new SHFILEINFO();
var shfiSize = (uint) Marshal.SizeOf(shfi.GetType());
IntPtr retVal = NativeMethods.SHGetFileInfo(
fileName, dwAttr, ref shfi, shfiSize,
((uint) (dwFlags) | (uint) iconState));
if (retVal.Equals(IntPtr.Zero))
{
//System.Diagnostics.Debug.Assert((!retVal.Equals(IntPtr.Zero)),"Failed to get icon index");
return 0;
}
else
{
return shfi.iIcon;
}
}
/// <summary>
/// Creates the SystemImageList
/// </summary>
void Create()
{
// forget last image list if any:
hIml = IntPtr.Zero;
if (IsXpOrAbove())
{
// Get the System IImageList object from the Shell:
var iidImageList = new Guid("46EB5926-582E-4017-9FDF-E8998DAA0950");
int ret = NativeMethods.SHGetImageList(
(int) size,
ref iidImageList,
ref iImageList
);
if( ret != 0) throw new ShellImageListException("Error getting image list. Return code: {0}, LastWin32Error: {1}", ret, Marshal.GetLastWin32Error());
// the image list handle is the IUnknown pointer, but
// using Marshal.GetIUnknownForObject doesn't return
// the right value. It really doesn't hurt to make
// a second call to get the handle:
var result = NativeMethods.SHGetImageListHandle((int) size, ref iidImageList, ref hIml);
if( result != 0 ) throw new ShellImageListException("Error getting image list. Return code: {0}, LastWin32Error: {1}", ret, Marshal.GetLastWin32Error());
}
else
{
// Prepare flags:
SHGetFileInfoConstants dwFlags = SHGetFileInfoConstants.SHGFI_USEFILEATTRIBUTES |
SHGetFileInfoConstants.SHGFI_SYSICONINDEX;
if (size == ShellImageListSize.SmallIcons)
{
dwFlags |= SHGetFileInfoConstants.SHGFI_SMALLICON;
}
// Get image list
var shfi = new SHFILEINFO();
var shfiSize = (uint) Marshal.SizeOf(shfi.GetType());
// Call SHGetFileInfo to get the image list handle
// using an arbitrary file:
hIml = NativeMethods.SHGetFileInfo(
".txt",
FILE_ATTRIBUTE_NORMAL,
ref shfi,
shfiSize,
(uint) dwFlags);
Debug.Assert((hIml != IntPtr.Zero), "Failed to create Image List");
}
}
internal static extern IntPtr SHGetFileInfo(
string pszPath,
int dwFileAttributes,
ref SHFILEINFO psfi,
uint cbFileInfo,
uint uFlags);
