The Windows Explorer can display
notification banners under certain conditions. They are displayed in the upper
area of the shell view, like this for example in the case of a failing network:
As you can see in this screenshot, a banner
can also contain a menu the end-user can open and use.
ShellBoost version 126.96.36.199 offers exclusive
support for this feature.
To display such a banner, you must override
methods of the ShellFolder class. This is demonstrated in the Registry
So, if you just want to display a message,
override the GetInformationBar method, like this, for example:
// this is called by ShellBoost
protected override InformationBar GetInformationBar()
// in this sample, we test the user has enough rights
if (Hive != RegistryHive.LocalMachine || DiagnosticsInformation.GetTokenElevationType() == TokenElevationType.Full)
var bar = new InformationBar();
// the guid identifies the banner, it must not be the empty guid.
// Use the same guid for one given banner.
bar.Guid = _adminMessageGuid;
// set the message that will be displayed to the end-user.
// it must not be null nor empty not whitespaces only
bar.Message = "You must be running with full priviledges to change anything here";
This is what’s displayed when the Shell
Folder is open:
In this screenshot, we also added a menu
(this is optional) like this:
protected override void CreateInformationBarMenu(InformationBar bar, ShellMenu appendMenu)
var item = new ShellMenuItem(appendMenu, "What is my UAC level?");
And the menu handling is done like this:
protected override async void HandleInformationBarMenu(InformationBar bar, IntPtr hwndOwner, int id)
if (id == 1) // first item has id 1, etc.
await WindowsUtilities.DoModelessAsync(() =>
System.Windows.Forms.MessageBox.Show(new Win32Window(hwndOwner), "UAC level is " + DiagnosticsInformation.GetTokenElevationType(), "Registry Folder");
Each menu item added to the banner menu is
automatically given an id that correspond to it’s insertion index.
The result is shown here:
Note the MessageBox here is a
modeless Window for your app (the ShellBoost Shell Folder server) but a modal
one for the Explorer Window.