multithreading in eventhandler?

Hello

For Sharepoint 2003 (SP2) I wrote an eventhandler wich assigns an unique number to a document when the INSERT event fires.

To avoid locking exceptions, the code loops until the file is no longer locked. Otherwise the document doesnt get a number.

This works OK, until someone locks a file, because all the other threads are waiting (with different documents) for the thread with the locked file.

I thought the threading mechanism for eventhandlers is parallel, but clearly it works like a stack.

How to avoid this? Do I have to write threading code?

Here's a snippet from the code:

System.Security.Principal.WindowsImpersonationContextwic =null;

wic =System.Security.Principal.WindowsIdentity.GetCurrent().Impersonate();

string_uniqueField =ReadSetting("RefUniqueField");

using (SPSite_site =newSPSite(EventInfo.Site.Url))

{

using (SPWeb_web =_site.OpenWeb())

{

System.Int64_uniqueId =this.GetUniqueId();

bool_error =true;

int_nrOfTries = 0;

while (_error && (_nrOfTries <= 1800) )

{

_error =false;

_nrOfTries++;

try

SPFile_file =_web.GetFile(EventInfo.UrlAfter);

_file =_web.GetFile(EventInfo.UrlAfter);

Debug("processing file " +_file.Name);

SPListItem_item =_file.Item;

_item[_uniqueField] =_uniqueId;

_item.Update();

}

catch (Exceptione)

{

EventLog.WriteEntry(_source,e.Message + "\n" +e.StackTrace,EventLogEntryType.Error);

_error =true;

Thread.Sleep(1000);

}

}

}

wic.Undo();

}

}

catch (Exceptione)

{

EventLog.WriteEntry(_source + " ",e.Message + "\n" +e.StackTrace,EventLogEntryType.Error);

}

[8075 byte] By [eddy2705] at [2008-1-1]