Dynamic select from a DropDownList

 Hello
I have a DropDownList that contains some dynamically loaded values. Depending on what I choose on that DropDownList, the next DropDownList will be filled with other items.
If there's only one item in the first DropDownList, how can I automatically select that and fill the next one by simulating a "click"? I always wants to use my onSelectedChanged methods so I guess I have to simulate a click. 
Have tried to use:


dropDownList1.SelectedIndex = 0;
dropDownList1_SelectedIndexChanged(Page, new EventArgs());
 But it won't fill the next dropdownlist in the same manner as manually clicking the DropDownList does..  Please help../henrik
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