GridView: Binding Database Fields to Textboxes

[MiziaQ]

I am connecting to a database table to pass values to textboxes in a gridview. I get the following error:

Object reference not set to an instance of an object.

Thanks in advance for your help!

private void ReadProjects()
    {

        SqlDataReader rdr;

        SqlConnection conn = new SqlConnection(WebConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString);

        SqlCommand cmd = new SqlCommand("SELECT * FROM Projects", conn);

        cmd.CommandType = CommandType.Text;

        int rowIndex = 0;

        if (ViewState["CurrentTable"] != null)
        {

            DataTable dtCurrentTable = (DataTable)ViewState["CurrentTable"];
            DataRow dr = null;

            if (dtCurrentTable.Rows.Count > 0)
            {

                for (int i = 1; i <= dtCurrentTable.Rows.Count; i++)
                {

                    TextBox box1 = (TextBox)Gridview1.Rows[rowIndex].Cells[1].FindControl("project_name");
                    TextBox box2 = (TextBox)Gridview1.Rows[rowIndex].Cells[2].FindControl("project_manager");
                    TextBox box3 = (TextBox)Gridview1.Rows[rowIndex].Cells[3].FindControl("team_members");
                    TextBox box4 = (TextBox)Gridview1.Rows[rowIndex].Cells[4].FindControl("status");

                    using (conn)
                    {
                        //open connection
                        conn.Open();

                        rdr = cmd.ExecuteReader();

                        while (rdr.Read())
                        {
                            dr = dtCurrentTable.NewRow();

                            box1.Text = rdr["ProjectName"].ToString();
                            box2.Text = rdr["ProjectID"].ToString();
                            box3.Text = rdr["CompanyID"].ToString();
                            box4.Text = rdr["Description"].ToString();

                            dtCurrentTable.Rows.Add(dr);

                            dtCurrentTable.AcceptChanges();
                        }
                    }

                    rowIndex++;

                }

                ViewState["CurrentTable"] = dtCurrentTable;


            }

       }

        else
        {

            Response.Write("ViewState is null");

        }

    }
}