/// <summary>
/// Starts listening for notifications in the specified registry key.
///
/// Each part of the key must be provided separately so that the watcher
/// can open its own handle.
/// </summary>
/// <param name="hive">The hive to watch</param>
/// <param name="view">The view to watch</param>
/// <param name="key">The key to watch</param>
/// <param name="handler">The event handler to invoke</param>
/// <param name="recursive">True to watch all subkeys as well</param>
/// <param name="notifyValueChange">
/// True to notify if a value is added, removed or updated.
/// </param>
/// <param name="notifyKeyChange">
/// True to notify if a subkey is added or removed.
/// </param>
/// <param name="tag">
/// An arbitrary identifier to include with any raised events.
/// </param>
/// <returns>An opaque token that can be pased to Remove.</returns>
public object Add(RegistryHive hive,
RegistryView view,
string key,
RegistryChangedEventHandler handler,
bool recursive = false,
bool notifyValueChange = true,
bool notifyKeyChange = true,
object tag = null)
{
if (key == null)
{
throw new ArgumentNullException("key");
}
if (handler == null)
{
throw new ArgumentNullException("handler");
}
if (!(notifyValueChange | notifyKeyChange))
{
throw new InvalidOperationException("Must wait for at least one type of change");
}
var args = new RegistryChangedEventArgs(
hive,
view,
key,
recursive,
notifyValueChange,
notifyKeyChange,
tag
);
int currentWatcher = -1;
RegistryWatcher watcher;
var token = AddInternal(handler, args);
while (token == null)
{
if (_extraWatchers == null)
{
_extraWatchers = new List <RegistryWatcher>();
}
currentWatcher += 1;
if (currentWatcher >= _extraWatchers.Count)
{
watcher = new RegistryWatcher();
_extraWatchers.Add(watcher);
}
else
{
watcher = _extraWatchers[currentWatcher];
}
token = watcher.AddInternal(handler, args);
}
return(token);
}
/// <summary>
/// Invokes the associated event handler.
/// </summary>
/// <returns>True if the watcher will be run again; false if the
/// entry has been closed and can be removed.</returns>
public bool Invoke(RegistryWatcher sender)
{
if (_key == null)
{
// Returns true so we don't try and remove null entries from
// the list.
return(true);
}
if (!_registered)
{
return(false);
}
_callback(sender, _args);
if (_args.CancelWatcher)
{
Unregister();
return(false);
}
lock (this) {
// only re-register if we haven't been closed
if (_registered)
{
try {
Register();
} catch (Win32Exception ex) {
// If we fail to re-register (probably because the
// key has been deleted), there's nothing that can
// be done. Fail if we're debugging, otherwise just
// continue without registering the watcher again.
Debug.Fail("Error registering registry watcher: " + ex.ToString());
_registered = false;
}
}
}
return(true);
}
/// <summary>
/// Invokes the associated event handler.
/// </summary>
/// <returns>True if the watcher will be run again; false if the
/// entry has been closed and can be removed.</returns>
public bool Invoke(RegistryWatcher sender) {
if (_key == null) {
// Returns true so we don't try and remove null entries from
// the list.
return true;
}
if (!_registered) {
return false;
}
_callback(sender, _args);
if (_args.CancelWatcher) {
Unregister();
return false;
}
lock (this) {
// only re-register if we haven't been closed
if (_registered) {
try {
Register();
} catch (Win32Exception ex) {
// If we fail to re-register (probably because the
// key has been deleted), there's nothing that can
// be done. Fail if we're debugging, otherwise just
// continue without registering the watcher again.
Debug.Fail("Error registering registry watcher: " + ex.ToString());
_registered = false;
}
}
}
return true;
}
/// <summary>
/// Starts listening for notifications in the specified registry key.
///
/// Each part of the key must be provided separately so that the watcher
/// can open its own handle.
/// </summary>
/// <param name="hive">The hive to watch</param>
/// <param name="view">The view to watch</param>
/// <param name="key">The key to watch</param>
/// <param name="handler">The event handler to invoke</param>
/// <param name="recursive">True to watch all subkeys as well</param>
/// <param name="notifyValueChange">
/// True to notify if a value is added, removed or updated.
/// </param>
/// <param name="notifyKeyChange">
/// True to notify if a subkey is added or removed.
/// </param>
/// <param name="tag">
/// An arbitrary identifier to include with any raised events.
/// </param>
/// <returns>An opaque token that can be pased to Remove.</returns>
public object Add(RegistryHive hive,
RegistryView view,
string key,
RegistryChangedEventHandler handler,
bool recursive = false,
bool notifyValueChange = true,
bool notifyKeyChange = true,
object tag = null) {
if (key == null) {
throw new ArgumentNullException("key");
}
if (handler == null) {
throw new ArgumentNullException("handler");
}
if (!(notifyValueChange | notifyKeyChange)) {
throw new InvalidOperationException("Must wait for at least one type of change");
}
var args = new RegistryChangedEventArgs(
hive,
view,
key,
recursive,
notifyValueChange,
notifyKeyChange,
tag
);
int currentWatcher = -1;
RegistryWatcher watcher;
var token = AddInternal(handler, args);
while (token == null) {
if (_extraWatchers == null) {
_extraWatchers = new List<RegistryWatcher>();
}
currentWatcher += 1;
if (currentWatcher >= _extraWatchers.Count) {
watcher = new RegistryWatcher();
_extraWatchers.Add(watcher);
} else {
watcher = _extraWatchers[currentWatcher];
}
token = watcher.AddInternal(handler, args);
}
return token;
}