code has not been effect on form load event .

Question

I have done coding of serial number in grid view in the load event of the form but when I am executing the form , The serial number code has not been shown  in data grid view . but  when same load event when I am calling from the button_Click event than Data grid view serial number is seen . why this happening ? 

 

Load event of form :

 

private void Frm_View_Upload_Paper_Load(object sender, EventArgs e)

{

      lan_id = que.language_ID();

      DataSet ds = new DataSet();

      string query = "Select * from VW_file_Upload_Download";

      ds = que.execute_query_with_ds(query, connection);

 

      if (ds.Tables[0].Rows.Count == 0)

            {

            DGV_View.DataSource = null;

            }

      else

            {

            DGV_View.DataSource = ds.Tables[0];

             sr_no start..

             int srno = 1;

             for (int i = 0; i < DGV_View.Rows.Count; i++)

                  {

                     DGV_View.Rows[i].Cells["Sr_No"].Value = srno;                  

                      srno = srno + 1;

                   }

            } 

 

} 

 

Button_Click Event :

 

private void button2_Click(object sender, EventArgs e)

         {

         Frm_View_Upload_Paper_Load(null, null);

         }