Dot in logger name is causing log4net to throw exception

[Sascha Hamacher]

Hello,
first of all thank you for the very good logging framework.
While working with Log4Net 1.2.10 I experienced the following problem:
When the logger name starts with a ".", LogManager.GetLogger fails with 
the following exception:

System.ArgumentOutOfRangeException was unhandled
Message="Index was out of range. Must be non-negative and less than the 
size of the collection.\r\nParameter name: startIndex"
Source="mscorlib"
ParamName="startIndex"
StackTrace:
     at System.String.LastIndexOf(Char value, Int32 startIndex, Int32 
count)
     at System.String.LastIndexOf(Char value, Int32 startIndex)
     at log4net.Repository.Hierarchy.Hierarchy.UpdateParents(Logger log)
     at log4net.Repository.Hierarchy.Hierarchy.GetLogger(String name, 
ILoggerFactory factory)
     at log4net.Repository.Hierarchy.Hierarchy.GetLogger(String name)
     at log4net.Core.LoggerManager.GetLogger(Assembly 
repositoryAssembly, String name)
     at log4net.LogManager.GetLogger(Assembly repositoryAssembly, 
String name)
     at log4net.LogManager.GetLogger(String name)
     at ReproCaseLog4Net.Program.Main(String[] args) in 
C:\Users\hamacs01\Documents\Visual Studio 
2008\Projects\ReproCaseLog4Net\ReproCaseLog4Net\Program.cs:line 20
     at System.AppDomain._nExecuteAssembly(Assembly assembly, String[] 
args)
     at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence 
assemblySecurity, String[] args)
     at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
     at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
     at System.Threading.ExecutionContext.Run(ExecutionContext 
executionContext, ContextCallback callback, Object state)
     at System.Threading.ThreadHelper.ThreadStart()
InnerException:


The following code of a simple command line program reproduces the 
problem for me:


using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using log4net.Appender;
using log4net.Config;
using log4net;
using log4net.Layout;

namespace ReproCaseLog4Net
{
class Program
{
  static void Main( string[] args )
  {
    BasicConfigurator.Configure( new ConsoleAppender()
    {
      Layout = new SimpleLayout()
    } );
    ILog log = LogManager.GetLogger( ".MyLogger" ); // <<--- the 
exception is thrown here
    log.Error( "ErrorMessage" );
    Console.ReadLine();
  }
}
}




Best regards,
Sascha Hamacher