question for drop down menu

[Anon]

Hi, I want to ask some question about drop down menu.

I have two drop down menu, I want to do that when I select "ABC" in the first menu, then I can select "a1","a2","a3" in the second menu. When I select "XYZ" in the first menu, then I can select "x1","x2" in the second menu. Can we do that??

[Anon]

sort of, but bear in mind that php is server side and the output as far as php is concerned is static i.e. you would have to re-submit arguments back into the page so php could populate the next selection box with the new values.
doing it dynamically client-side would involve using javascript which php can output just like it does with html.
javascript can use the onchange() method called from the first selection box to populate the second. if your looking for source code example there are plenty of javascript sites
hope this helps

[Anon]

Then where I can find the example of this kind of javascripts? I think it may be helpful for my website design, may you tell me where I can get it? Thkx.