获取选择的用户集合

private SPUserCollection GetSelectUser()
        {
            SPUserCollection users = null;
            if (userEditor.IsValid)
            {
                string[] strLoginNames = new string[userEditor.Entities.Count];
                for(int nA = 0; nA < userEditor.Entities.Count; nA++)
                {
                    strLoginNames[nA] = ((PickerEntity)userEditor.Entities[nA]).Key;
                }

                users = SPContext.Current.Web.SiteUsers.GetCollection(strLoginNames);
                if (users.Count == 0 )
                {
                    users = null;
                }
            }
            return users;
        }