Deleting all library items in a document library using SpWeb and Batch

private static void DeleteAllItemsUsingBatch()  

        {  

            using (SPSite site = new SPSite("http://mysharepointserver"))  

            {  

                SPWeb web = site.OpenWeb("/");  

                SPList list = web.Lists["Documents"];  

                StringBuilder sb = new StringBuilder();  

                sb.Append("<batch>");  

                string batchCommand = "<method><setlist scope=\"Request\">" + list.ID + "</setlist><setvar name=\"ID\">{0}</setvar><setvar name=\"Cmd\">DELETE</setvar><setvar name=\"owsfileref\">{1}</setvar></method>";  

                foreach (SPListItem item in list.Items)  

                {  

                    sb.AppendFormat(batchCommand, item.ID.ToString(), item.File.ServerRelativeUrl);  

                }  

                sb.Append("</batch>");  

  

                web.AllowUnsafeUpdates = true;  

                site.RootWeb.ProcessBatchData(sb.ToString());  

                web.AllowUnsafeUpdates = false;  

                web.Close();  

            }  

        }