再次 求助~！！感激不尽

Question

public List<Model.GrabSet> GrapAll()
        {
            List<Model.GrabSet> list = new List<InfoSpilder.Model.GrabSet>();
            Model.GrabSet graps = null;            string sql = "select * from grabset";
            DataSet ds = SqlHelper.ExecuteDataset(sql);
            for (int i = 0; i < ds.Tables[0].Rows.Count; i++){
                graps = new InfoSpilder.Model.GrabSet();                if (ds.Tables[0].Rows.Count > 0 )
                {
                graps.typeid = ds.Tables[0].Rows[i]["typeid"].ToString().Trim();
               graps.itemName = ds.Tables[0].Rows[i]["itemName"].ToString().Trim();
               graps.AreaStart = ds.Tables[0].Rows[i]["AreaStart"].ToString().Trim();
               graps.AreaEnd = ds.Tables[0].Rows[i]["AreaEnd"].ToString().Trim();
               graps.addWord = ds.Tables[0].Rows[i]["addWord"].ToString();
               graps.delWord = ds.Tables[0].Rows[i]["delWord"].ToString().Trim();
               graps.matchItem = ds.Tables[0].Rows[i]["matchItem"].ToString();
               graps.matchTable = ds.Tables[0].Rows[i]["matchTable"].ToString().Trim();
               graps.orderid = ds.Tables[0].Rows[i]["orderid"].ToString().Trim();
                graps.createDate = DateTime.Parse(ds.Tables[0].Rows[i]["createDate"].ToString().Trim());
                graps.modifyDate = DateTime.Parse(ds.Tables[0].Rows[i]["modifyDate"].ToString().Trim());                graps.mender = ds.Tables[0].Rows[i]["mender"].ToString().Trim();
                graps.creator = ds.Tables[0].Rows[i]["creator"].ToString().Trim();
                graps.deleteFlag = ds.Tables[0].Rows[i]["deleteFlag"].ToString().Trim();
                
                list.Add(graps);
                }
            }
            return list;
        }
说我没有 graps.typeid = ds.Tables[0].Rows[i]["typeid"].ToString().Trim(); 
报错：异常详细信息: System.NullReferenceException: 未将对象引用设置到对象的实例。
怎么整啊！！！

Answer 1

string sql = "select * from grabset";
DataSet ds = SqlHelper.ExecuteDataset(sql);
你调试下上面的代码能取到值吗,好像没有connection阿

Answer 2

graps = new InfoSpilder.Model.GrabSet();GrabSet返回的是什么类型呢