RowCommand 中DataItem的问题

Question

 protected void gdvMain_RowCommand(object sender, GridViewCommandEventArgs e)
    {
        string  = string.Empty;
        if (e.CommandArgument != null)
        {
             = e.CommandArgument.ToString();
        }        if (e.CommandName.Equals("Mark")&&!.Equals("YZ"))
        {
            GridViewRow gvrow = ((e.CommandSource as ImageButton).NamingContainer) as GridViewRow;
            int id = 0;
            if (gvrow != null)
            {
                DataRowView drvMain = gvrow.DataItem as DataRowView;
                if (drvMain != null)
                {
                    int.TryParse(Convert.ToString(drvMain["ID"]), out id);
                }
            }            PeprisOA.Model.CashCall modelCash = new PeprisOA.Model.CashCall();
            PeprisOA.BLL.CashCall managerCash = new PeprisOA.BLL.CashCall();
            modelCash = managerCash.GetModel(id);            if (modelCash != null)
            {
                switch ()
                {
                    case "WS":
                        modelCash.FsValue = "CS";
                        break;
                    case "CS":
                        modelCash.FsValue = "FS";
                        break;
                    case "FS":
                        modelCash.FsValue = "FH";
                        break;
                    case "FH":
                        modelCash.FsValue = "YZ";
                        break;
                    default:
                        modelCash.FsValue = "CS";
                        break;
                }
                if (managerCash.Update(modelCash))
                {
                    PeprisOA.Common.JsUtil.Alert(this, "批复成功!");
                }
                else
                {
                    PeprisOA.Common.JsUtil.Alert(this, "批复失败,请重新批复!");
                }
            }
        }
代码如上，为什么DataRowView drvMain = gvrow.DataItem as DataRowView;的DataItem为Null？

Answer 1

跟踪过了，DataItem确实为Null，我是想知道这是为什么？按说只要有过DataBind之后DataItem就能得到，为什么是Null呢？

Answer 2

换了种方法，问题已解决…粘上代码…
前台放了个隐藏域，值绑定Id，后台Command事件中获取控件，取得Id GridViewRow gvrow = ((e.CommandSource as ImageButton).NamingContainer) as GridViewRow;
            
            int id = 0;
            if (gvrow != null)
            {
                HiddenField hfId=gvrow.FindControl("hfId") as HiddenField;
                if (hfId != null)
                {
                    int.TryParse(Convert.ToString(hfId.Value), out id);
                }
            }

Answer 3

其实我还是想问，为什么DataItem为Null呢？求解，求解…

Answer 4

绑定代码写在回发里吧  IsPostBack这样回发的时候  不会触发绑定， 值是从ViewState中取的

Answer 5

恩，楼上说的很有可能，但是我没试…不过 ，应该是这样的…在每次获取DataItem之前必须要重新触发DataBind事件…