Hi everybody,

Do you know how can I add a custom property to a control?

Here is the code I'm trying

protected void Page_Load(object sender, EventArgs e)
    {
        string sConnString = ConfigurationManager.ConnectionStrings["FCCMSConnectionString"].ConnectionString;
        SqlConnection oCn = new SqlConnection(sConnString);

        SqlCommand Command = new SqlCommand("GetSchoolsBySiteID", oCn);
        Command.CommandType = CommandType.StoredProcedure;

        SqlParameter ParSiteID = new SqlParameter("@SiteID", this.GetParameter());
        
        Command.Parameters.Add(ParSiteID);
        
        Command.Connection.Open();

        SqlDataReader oReader = Command.ExecuteReader();
        
        while (oReader.Read())
        {
         ListItem li = new ListItem();
           li.Attributes.Add("Phone", oReader["Phone"].ToString()) ;
           li.Text = oReader["School"].ToString() ; 
           li.Value = li.Text;
           this.ddlSchool.Items.Add(li);   
        }
        oReader.Close();
        oCn.Close();
        this.ddlSchool.Attributes.Add("onchange","alert( this.options[this.selectedIndex].Phone);");  
    }

However, JavaScript shows undefined all the time. Do you see what's wrong here or how can I create a new custom property and access it?

Thanks in advance.