foreach (GridViewRow grdRow in GridView1.Rows)
{
using (SqlConnection conn = (SqlConnection)provider.CreateConnection())
{
conn.ConnectionString = connString;
using (SqlCommand cmd = new SqlCommand())
{
DropDownList NewsType;
NewsType = (DropDownList)(GridView1.Rows[grdRow.RowIndex].FindControl("NewsletterType"));
string Newslettertype = NewsType.SelectedItem.Text;

string title = GridView1.Rows[grdRow.RowIndex].Cells[1].Text;

string sqlQuerry = "Update Newsletter set NewsletterType='" + Newslettertype + "', " +
"ModifiedDate='" + DateTime.Now + "', ModifiedBy = '" + Page.User.Identity.Name + "' where Title='" + title + "' ";
cmd.CommandText = sqlQuerry;
cmd.CommandType = CommandType.Text;

conn.Open();
cmd.Connection = conn;
cmd.ExecuteNonQuery();
}
}
}