To get your <form> result sent as an array to your PHP script you name the <input>, <select> or <textarea> elements like this:
<input name="catlist[]">
<input name="catlist[]">
<input name="catlist[]">
<input name="catlist[]">
Treat the received information in your PHP script like this:
$num_cat = count ($catlist);
for ($i = 0; $i < $num_cat; $i++) {
... $catlist[$i] ...
}
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