Compiler Error CS1038

#endregion directive expected

A #region directive did not have a matching #endregion directive.

The following sample generates CS1038:

// CS1038.cs  
#region testing  
  
public class clx  
{  
   public static void Main()  
   {  
   }  
}  
// CS1038  
// uncomment the next line to resolve  
// #endregion