Well in that case you need a default value so that you always fire the onchange:
Code:
<select name="book_date" id="book_date" onChange="form.submit()">
<option value="">Choose a date</option>
<option value="<%=date()%>">Today</option>
<option value="<%=date()-1%>">1 day ago</option>
<option value="<%=date()-2%>">2 days ago</option>
<option value="<%=date()-3%>">3 days ago</option>
<option value="<%=date()-4%>">4 days ago</option>
<option value="<%=date()-5%>">5 days ago</option>
</select>
You will then have to have an onsubmit handler on the form to check that the selectedIndex of the list is greater than 0.
Personally I think this is poor UI design, it's all too easy to choose the wrong option from a selectbox but now the form submits automatically. Better to make them pick a date and click a submit button when they can see they chose correctly.
--
Joe (
Microsoft MVP - XML)
