Feeding a value in a dropdown list to another dropdown list
 

hihi,

can someone help me with this problem;

i want to be able to feed a value from a dropdown list A as a condition for items in dropdown list B. both dropdown list are in the same form. the values for both dropdown list are extracted from my mysql database.

i've tried to refreshing the page with javascript with this

function update(theForm){
location.href = location + "?Category=" + theForm.CategoryName.value }

this works fine if i only click once on dropdown list A but the if i happen to click again from dropdown list A, then the link would be something like "http://localhost/product.php?Category=food?Category=drink"

how to i replace the category argument value?

thanks in advance