Export DataSet to XML
DataSet ds = new DataSet();
ds = _customers.GetCustomers();
ds.WriteXml("D:\\Customers.xml", System.Data.XmlWriteMode.IgnoreSchema);
Export DataTable to XML
DataTable dt = new DataTable();
dt = _customers.GetCustomers();
DataSet ds = new DataSet();
ds.Tables.Add(dt);
ds.WriteXml("D:\\Customers.xml", System.Data.XmlWriteMode.IgnoreSchema);