/// <summary>
/// Creates the SystemImageList
/// </summary>
private void create()
{
// forget last image list if any:
hIml = IntPtr.Zero;
if (isXpOrAbove())
{
// Get the System IImageList object from the Shell:
Guid iidImageList = new Guid("46EB5926-582E-4017-9FDF-E8998DAA0950");
int ret = Shell32.SHGetImageList((int)size, ref iidImageList, ref iImageList);
// 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:
Shell32.SHGetImageListHandle((int)size, ref iidImageList, ref hIml);
}
else
{
// Prepare flags:
SHGFI dwFlags = SHGFI.UseFileAttributes | SHGFI.SysIconIndex;
if (size == SysImageListSize.smallIcons)
{
dwFlags |= SHGFI.SmallIcon;
}
// Get image list
ShFileInfo shfi = new ShFileInfo();
uint shfiSize = (uint)Marshal.SizeOf(shfi.GetType());
// Call SHGetFileInfo to get the image list handle
// using an arbitrary file:
hIml = Shell32.SHGetFileInfo(".txt", FileAttributes.Normal, ref shfi, (int)shfiSize, dwFlags);
System.Diagnostics.Debug.Assert((hIml != IntPtr.Zero), "Failed to create Image List");
}
}
/// <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)
{
SHGFI dwFlags = SHGFI.SysIconIndex;
FileAttributes dwAttr;
if (size == SysImageListSize.smallIcons)
{
dwFlags |= 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 |= SHGFI.UseFileAttributes;
dwAttr = FileAttributes.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"
ShFileInfo shfi = new ShFileInfo();
uint shfiSize = (uint)Marshal.SizeOf(shfi.GetType());
IntPtr retVal = Shell32.SHGetFileInfo(fileName, dwAttr, ref shfi, (int)shfiSize, (SHGFI)((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.IconIndex;
}
}
