同步取得GricdView中更新的数据

　　编程中好多时候都会遇到要根据GricdView中的数据更新到数据库中,就会带来一个问题:如何取得GricdView中的新数据?下面提供一种解决此问题的方法:

 private DataTable SyncGricdViewSelectedItemToSession()
        {
           
            dt = (DataTable)Session[SearchResultDt]; //取得要更新的Session DataTable
            

　　　　 //定义一个key
            DataColumn[] keys = new DataColumn[2];
            DataColumn fpn_numcolumn = dt.Columns["NUM"];
            DataColumn transactionidcolumn = dt.Columns["TransactionID"];
            keys[0] = fpn_numcolumn;
            keys[1] = transactionidcolumn;
            dt.PrimaryKey = keys;

　　　　 //-------------

            CheckBox chkSelect = null;
            TextBox txtDishAmount = null;
            Label lblDishonoredAmount = null;
            string sNum = null;
            string sTransactionid = null;
            string[] tempkeys = null;
            bool isEnableAmonut = false;
            bool isShow = false;
            DataRow dr = null;

            CheckBox chkSelectAll = (CheckBox)gvResult.HeaderRow.FindControl("chkSelectAll");
            if (chkSelectAll.Checked)
            {
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    isEnableAmonut = Convert.ToBoolean(dt.Rows[i]["EnableAmonut"].ToString().Trim());
                    isShow = Convert.ToBoolean(dt.Rows[i]["HasShow"].ToString().Trim());
                    if (isShow && isEnableAmonut)
                    {
                        dt.Rows[i]["chkSelect"] = "true";

                        if (i < gvResult.Rows.Count)
                        {
                            chkSelect = (CheckBox)gvResult.Rows[i].FindControl("chkSelect");
                            txtAmount = (TextBox)gvResult.Rows[i].FindControl("txtAmount");
                            lblAmount = (Label)gvResult.Rows[i].FindControl("lblAmount");
                            sNum = ((HiddenField)gvResult.Rows[i].FindControl("hdno")).Value;
                            sTransactionid = ((HiddenField)gvResult.Rows[i].FindControl("hdftransactionid")).Value;
                            tempkeys = new string[] { sNum, sTransactionid };
                            dr = dt.Rows.Find(tempkeys);
                            if (dr != null)
                            {                               
                                if (isEnableAmonut)
                                {
                                    if (dr["Amount"].ToString() == "")  
                                    {
                                        dr["Amount"] = txtAmount.Text.Trim().Replace(",", "");
                                        dt.Rows[i]["chkSelect"] = "True"; 
                                    }
                                }
                                else
                                {
                                    if (dr["Amount"].ToString() == "")  
                                    {
                                        dr["Amount"] = lblAmount.Text.Trim().Replace(",", "");
                                    }
                                }
                            }
                        }
                    }
                    else
                    {
                        dt.Rows[i]["chkSelect"] = "false";
                    }
                }
            }
            else
            {
                //check those selected items.
                for (int j = 0; j < gvResult.Rows.Count; j++)
                {
                    isEnableAmonut = Convert.ToBoolean(((HiddenField)gvResult.Rows[j].FindControl("hdfEnableAmonut")).Value);
                    chkSelect = (CheckBox)gvResult.Rows[j].FindControl("chkSelect");
                    txtAmount = (TextBox)gvResult.Rows[j].FindControl("txtAmount");
                    lblAmount = (Label)gvResult.Rows[j].FindControl("lblAmount");
                    sNum = ((HiddenField)gvResult.Rows[j].FindControl("hdno")).Value;
                    sTransactionid = ((HiddenField)gvResult.Rows[j].FindControl("hdftransactionid")).Value;
                    tempkeys = new string[] { sNum, sTransactionid };
                    dr = dt.Rows.Find(tempkeys);
                    if (dr != null)
                    {
                        dr["chkSelect"] = chkSelect.Checked.ToString();
                        if (isEnableAmonut)
                        {
                            dr["Amount"] = txtAmount.Text.Trim().Replace(",", "");
                        }
                        else
                        {
                            dr["Amount"] = lblAmount.Text.Trim().Replace(",", "");
                        }
                    }
                }
            }
           
            return dt;

        }