update OnMessageReceived

MediaBrowser.Dlna/Ssdp/SsdpHandler.cs

@@ -87,11 +87,12 @@ namespace MediaBrowser.Dlna.Ssdp
         public event EventHandler<SsdpMessageEventArgs> MessageReceived;
 
         private async void OnMessageReceived(SsdpMessageEventArgs args)
-        {
-            if (string.Equals(args.Method, "M-SEARCH", StringComparison.OrdinalIgnoreCase))
         {
             var headers = args.Headers;
+            string st;
 
+            if (string.Equals(args.Method, "M-SEARCH", StringComparison.OrdinalIgnoreCase) && headers.TryGetValue("st", out st))
+            {
                 TimeSpan delay = GetSearchDelay(headers);
 
                 if (_config.GetDlnaConfiguration().EnableDebugLogging)
@@ -101,12 +102,8 @@ namespace MediaBrowser.Dlna.Ssdp
 
                 await Task.Delay(delay).ConfigureAwait(false);
 
-                string st;
-                if (headers.TryGetValue("st", out st))
-                {
                 RespondToSearch(args.EndPoint, st);
             }
-            }
 
             EventHelper.FireEventIfNotNull(MessageReceived, this, args, _logger);
         }