int a;
con = new SqlConnection("Data Source=DPSINTERIOR;Initial Catalog=studentzone;Persist Security Info=True;User ID=sa;Password=sa");
con.Open();
cmd = new SqlCommand("Select MAX(Student_id) from studentd", con);
dr = cmd.ExecuteReader();
if (dr.Read())
{
string val = dr.GetInt32(0).ToString();
if (val == "")
textBox1.Text = "1";
}
else
a = Convert.ToInt32(dr[0].ToString());
a = a + 1;
textBox1.Text = a.ToString();
i have no data in database. i want to auto generate number in first textbox1 column.....but i found this error "Data is Null. This method or property cannot be called on Null values." how can i solve this problem??????????