ASP.NET Link MsSQL

SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["DefirekingConnectionString1"].ConnectionString);
       
        string sqlQueryProviderName = "Select TOP 1 provider_name From Defireking.dbo.provider where provider_id = '" + provider.Text + "'";
        SqlCommand cmd = new SqlCommand(sqlQueryProviderName);
        SqlDataReader dr = cmd.ExecuteReader();
        String provider_name;
        while (dr.Read()) // 迴圈會執行到沒有下一筆資料為止
        {
            provider_name = dr["provider_name"].ToString();
        }