what does "snapshot out of sync" mean?

hi i'm developing web game with ur Unity3d and SmartFoxServer technology.
as u provided nice example, it's very comfortable to understand co-operation of both server and client.

but here i have a problem with my code.
plz read debug message below:

Code (csharp):

1. InvalidOperationException: Hashtable.Enumerator: snapshot out of sync.
2. System.Collections.Hashtable+Enumerator.FailFast ()
3. System.Collections.Hashtable+Enumerator.MoveNext ()
4. LobbyGUI.SetupRoomList ()   (at Assets\Game\Scripts\LobbyGUI.cs:206)
5. LobbyGUI.Awake ()   (at Assets\Game\Scripts\LobbyGUI.cs:66)

this exception happens when i typed username and press submit button in login user interface.
and strangely this exception happens often, not always.

and the code LobbyGUI.cs:66 is like this:

Code (csharp):

1.     private void SetupRoomList() { 
2.         List<string> rooms = new List<string>();
3.  
4.         foreach ( Room room in smartFox.GetAllRooms().Values ) {
5.  
6.             // Only show game rooms
7.             if ( !room.IsGame()) {
8.                 continue;
9.             }
10.  
11.             Debug.Log("Room id: " + room.GetId() + " has name: " + room.GetName());
12.  
13.             rooms.Add(room.GetName());
14.         } //////////// this is line 66
15.  
16.         roomStrings = rooms.ToArray();
17.     }

this code is totally from example except i transported it to my own project.
i cannot understand why this exception happens and even i don't know what "snapshot out of sync" means.

plz someone tell me how i can solve these problem.
i cannot go any further by the virtue of this bug thx...

 

Just a thought,

Are you managing the exceptions when your client cannot connect to your server?, are you managing timeouts from the server?

as I told you its just a thought as I'm not an expert in smartfox , but this might be a reason of that problem you are having, as it happens often

 

well connection to the server is established in the previous step of writing username and password.
because smartFox.IsConnected() is true in login interface, so i think it's totally safe to proceed
from connection step to login step.

but the connection status can be a problem as u said i will check it up again. smartFox.GetAllRooms() may throw exception

thank you!

 

I ran into the same problem using two functions
one was an iterator through a hashtable.
The sub function was trying to save data in the hashtable.

Code (csharp):

1.  
2. function a() {
3.     for ( var name_str : String in myhash.Keys ) {
4.            
5.             result_str = dostuff(name_str);
6.            
7.     }
8. }
9.  
10. function dostuff(name_str : String) {
11.     var result_str = myhash[name_str]
12.  
13.     myhash[name_str] = "try this";
14.  
15.     return result_str;
16. }

the solution that worked for me was:
don't store data in the hashtable while I was iterating through it

 

I'm getting the same thing but all I'm doing is reading from a SortedList

Code (csharp):

1. for (var key in globals.hidden.list.Keys) {
2.             globals.hidden.list[key].active = false;
3.         }
4.  

Oddly too this has only been a problem since moving to Unity 3 from 2.6