public IChangeToken Watch(string filter)
{
if (filter.IndexOf('*') >= 0)
{
throw new ArgumentException($"Wildcards are not allowed", nameof(filter));
}
var filePath = Path.Combine(_root, filter);
lock (_gate)
{
if (_changeTokens == null)
{
_changeTokens = new Dictionary <string, PollingFileChangeToken>(StringComparer.OrdinalIgnoreCase);
}
if (!_changeTokens.TryGetValue(filePath, out var changeToken))
{
changeToken = new PollingFileChangeToken(filePath);
_changeTokens.Add(filePath, changeToken);
}
return(changeToken);
}
}
public DisposableChangeCallback(PollingFileChangeToken pollingFileChangeToken, int callbackId)
{
_changeToken = pollingFileChangeToken;
_callbackId = callbackId;
}