RowCreated shows error on posback

Question

User1052662409 posted

Hi All,

I am trying to show subtotal in gridview group by dates. Here I used gridview's RowCreated  event,

When I binding the gridview it's working fine, but when I try to add another row to grid by clicking a button it shows null reference error on postback.

 protected void GVCash_RowCreated(object sender, GridViewRowEventArgs e)
    {
        subTotal_cash = 0;
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
           
            DataTable dt = (e.Row.DataItem as DataRowView).DataView.Table;
            DateTime date = Convert.ToDateTime(dt.Rows[e.Row.RowIndex]["date"]);
            total_cash += Convert.ToDecimal(dt.Rows[e.Row.RowIndex]["opening_balance"]);
            if (date != currentId_cash)
            {
                if (e.Row.RowIndex > 0)
                {
                    for (int i = subTotalRowIndex_cash; i < e.Row.RowIndex; i++)
                    {
                        subTotal_cash += Convert.ToDecimal(GVCash.Rows[i].Cells[1].Text);
                    }
                    this.AddTotalRow_cash(subTotal_cash.ToString());
                    subTotalRowIndex_cash = e.Row.RowIndex;
                }
                currentId_cash = date;
            }
        }
    }

On this DataTable dt = (e.Row.DataItem as DataRowView).DataView.Table; line it shows the null reference error.

Pls suggest.

Answer 1

User-330142929 posted

Hi Mukesh1,

When I binding the gridview it's working fine, but when I try to add another row to grid by clicking a button it shows null reference error on postback.

According to your description, when the page is resubmitted to the server, if you do not perform a rebind  function in page_load, it is flushed as soon as it refreshes, or you do not put the Gridview binding event in the If(!ispostback), the row_created event  parameter will get a null reference.

So I suggest you bind the data in page_load, just like this:

 

protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                this.GridView1.DataSource = GetDataTable();
                this.GridView1.DataBind();
            }
        }

If the solution could not solve your problem, please feel free to let me know.

 

Best Regards,

Abraham