SQL Select Query in ASP.Net

Question

I have a table that contains information like(examId, examActive) and I want  to display a particular examId in a textbox. I am new in ASP.Net and SQL. Please Help me. Here is my code, what else I have to do.



vcon.Open();

            SqlDataAdapter da = new SqlDataAdapter("select examId from ExamConfig where examActive='1'", vcon);

            DataTable dt = new DataTable();
            DataSet ds = new DataSet();
            da.Fill(ds);


            txtExamId.Text = dt.Rows[1]["examId"].ToString();


vcon.Close();