1public SPUser GetSPUser(SPListItem item, Guid key)
2        {
3            SPFieldUser field = item.Fields[key] as SPFieldUser;
4
5            if (field != null)
6            {
7                if (item[key] != null)
8                {
9                    SPFieldUserValue fieldValue = field.GetFieldValue(item[key].ToString()) as SPFieldUserValue;
10                    if (fieldValue != null)
11                    {
12                        return fieldValue.User;
13                    }
14                }
15            }
16            return null;
17        }