/// <summary>
/// Populates the Open With menu and returns a <see cref="NativeMenu"/> object.
/// </summary>
/// <param name="fileName">The file name whose menu to retrieve.</param>
/// <param name="openWithCmd">The menu item id of the Open With menu item of the parent menu.</param>
/// <param name="hMenu">The handle of the parent menu.</param>
/// <returns></returns>
public static NativeMenu GetOpenWithMenu(string fileName, IntPtr openWithCmd, IntPtr hMenu)
{
// Create a native context menu submenu populated with "open with" items
var col = new MenuItemBagCollection();
var nm = new NativeMenu(hMenu);
string ext = Path.GetExtension(fileName).ToLower();
NativeMenuItem nmi;
var assoc = NativeShell.EnumFileHandlers(ext);
nm.Items.Clear();
if (assoc is null)
{
nm.Destroy();
return(null);
}
foreach (IAssocHandler handler in assoc)
{
Icon icn;
string pth = null;
int idx;
string uiname = null;
string pathname = null;
handler.GetIconLocation(out pth, out idx);
int iix = (int)NativeShell.Shell_GetCachedImageIndex(pth, idx, 0U);
icn = Resources.GetFileIconFromIndex(iix, (Resources.SystemIconSizes)(int)(User32.SHIL_SMALL));
handler.GetName(out pathname);
if (File.Exists(pathname) == false)
{
continue;
}
handler.GetUIName(out uiname);
if (icn is null)
{
nmi = nm.Items.Add(uiname);
}
else
{
nmi = nm.Items.Add(uiname, icn);
}
col.Add(new MenuItemBag(nmi, handler));
}
nm.Items.Add(null);
nmi = nm.Items.Add("&Choose default program...");
nmi.Id = (int)openWithCmd;
nm.Bag = col;
return(nm);
}