Home/ Questions/Q 7717735
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-01T02:58:42+00:00

I have a datagridview in c# that i am filling from a mysql database.

  • 0

I have a datagridview in c# that i am filling from a mysql database. The user reviews the info and then saves it to a different mysql database. I know the connections to both work and like my title says I’m getting a null exception on the first string in the for loop.

there are only 6 columns in the row and the only thing i can think of is i am looking at rows and not columns but not sure what the code should be for that edit I changed it as most had said to < instead of <= and I know why i get the error but don’t know how to get the information i need. The error is coming from the fact that the cell shows as null even though there is a value in the cell.

string ConnectionString2 = ConfigurationSettings.AppSettings["ConnectionString2"];
MySqlConnection connection2;
connection2 = new MySqlConnection(ConnectionString2);

int i;
for (i = 0; i < dataGridView1.Rows.Count; i++)
{
    string day = dataGridView1.Rows[i].Cells[0].Value.ToString();
    string Desc = dataGridView1.Rows[i].Cells[1].Value.ToString();
    string item = dataGridView1.Rows[i].Cells[2].Value.ToString();
    string prod = dataGridView1.Rows[i].Cells[3].Value.ToString();
    string vol = dataGridView1.Rows[i].Cells[4].Value.ToString();
    string qty = dataGridView1.Rows[i].Cells[5].Value.ToString();

    MySqlCommand cmdwk = new MySqlCommand("INSERT INTO spt_proposal_line_lab (proposal_Id,day_Name,proposal_Desc,proposal_Vol,product_Id,proposal_Qty,item_Id) VALUES (@propid,@day,@desc,@vol,@prod,@qty,@item)", connection2);
    MySqlParameter propid = new MySqlParameter("@propid", b);
    MySqlParameter day1 = new MySqlParameter("@day", day);
    MySqlParameter Desc1 = new MySqlParameter("@desc", Desc);
    MySqlParameter vol1 = new MySqlParameter("@vol", vol);
    MySqlParameter prod1 = new MySqlParameter("@prod", prod);
    MySqlParameter qty1 = new MySqlParameter("@qty", qty);
    MySqlParameter item1 = new MySqlParameter("@item", item);

    cmdwk.Parameters.Add(day1);
    cmdwk.Parameters.Add(propid);
    cmdwk.Parameters.Add(Desc1);
    cmdwk.Parameters.Add(prod1);
    cmdwk.Parameters.Add(vol1);
    cmdwk.Parameters.Add(qty1);
    cmdwk.Parameters.Add(item1); 
}

The datagrid is called and filled in the load this is done on a button
Edit Seeing I am one point away from my img post ability I will try to explain this more
When the button is clicked and this code runs the error comes up at

string day = dataGridView1.Rows[i].Cells[0].Value.ToString();

the error is

Object reference not set to an instance of an object.

System.NullReferenceException was unhandled
  HResult=-2147467261
   Message=Object reference not set to an instance of an object.
    Source=SpectLabRemake2
    StackTrace:
   at SpectLabRemake2.Form6.btn_Save_Click(Object sender, EventArgs e)
Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    Well for everyone that has this problem I will post my code that fixed the issue and Thank YOU soo much to everyone that was SOOOO helpful here with this issue.

      for (i = 0; i < dataGridView1.Rows.Count-1; i++)
        {

            string ConnectionString2 = ConfigurationSettings.AppSettings["ConnectionString2"];
            MySqlConnection connection2;








            connection2 = new MySqlConnection(ConnectionString2);
            connection2.Open();


                string day = dataGridView1.Rows[i].Cells[0].Value.ToString();
                string Desc = dataGridView1.Rows[i].Cells[1].Value.ToString();
                string item = dataGridView1.Rows[i].Cells[2].Value.ToString();
                string prod = dataGridView1.Rows[i].Cells[3].Value.ToString();
                string vol = dataGridView1.Rows[i].Cells[4].Value.ToString();
                string qty = dataGridView1.Rows[i].Cells[5].Value.ToString();


                MySqlCommand cmdwk = new MySqlCommand("INSERT INTO spt_proposal_line_lab (proposal_Id,day_Name,proposal_Desc,proposal_Vol,product_Id,proposal_Qty,item_Id) VALUES (@propid,@day,@desc,@vol,@prod,@qty,@item)", connection2);
                MySqlParameter propid = new MySqlParameter("@propid", b);
                MySqlParameter day1 = new MySqlParameter("@day", day);
                MySqlParameter Desc1 = new MySqlParameter("@desc", Desc);
                MySqlParameter vol1 = new MySqlParameter("@vol", vol);
                MySqlParameter prod1 = new MySqlParameter("@prod", prod);
                MySqlParameter qty1 = new MySqlParameter("@qty", qty);
                MySqlParameter item1 = new MySqlParameter("@item", item);

                cmdwk.Parameters.Add(day1);
                cmdwk.Parameters.Add(propid);
                cmdwk.Parameters.Add(Desc1);
                cmdwk.Parameters.Add(prod1);
                cmdwk.Parameters.Add(vol1);
                cmdwk.Parameters.Add(qty1);
                cmdwk.Parameters.Add(item1);
                cmdwk.ExecuteNonQuery();



            }
        }

    }
}

    Brent

    • 0