A minor modification of the “Programmatic.aspx” reference sample file need to be made in order to make the combo accessible from server side event.

Please try to put the declaration of the combo object as a global variable rather than put the line in Page_Load server side event.

Original:

AccessDataSource access;

protected void Page_Load(object sender, EventArgs e)
{
    access = new AccessDataSource(Server.MapPath("./App_Data/Northwind.mdb"),
        "Select * from Customers");
    access.ID = "AccessDataSource1";

    WebCombo combo = new WebCombo("WebCombo1");
    ...

Modified version:

AccessDataSource access;
WebCombo combo = new WebCombo("WebCombo1");

protected void Page_Load(object sender, EventArgs e)
{
    access = new AccessDataSource(Server.MapPath("./App_Data/Northwind.mdb"),
        "Select * from Customers");
    access.ID = "AccessDataSource1";
    ...

In order to obtain the selected value when submit button is pressed can be simply acquired by using following snippet code.

combo.Value

Hope this helps.

Great! Thanks Yudi.