How do I check if there are any records found after filter search ASP.NET C#

try
        {
            string strConnString = ConfigurationManager.ConnectionStrings["ConnStr"].ConnectionString;
            SqlConnection con = new SqlConnection(strConnString);
            DataTable dt = new DataTable();

            using (SqlConnection conn = new SqlConnection(strConnString))
            {
                string strQuery = "SELECT * FROM TDLoanRate where LoanType Like'" + txtValue.Text + "%'";
                SqlCommand cmd = new SqlCommand(strQuery);
                using (SqlDataAdapter sda = new SqlDataAdapter())
                {
                    cmd.Connection = con;
                    conn.Open();
                    sda.SelectCommand = cmd;
                    sda.Fill(dt);
                    GridView2.DataSource = dt;
                    GridView2.DataBind();
                }