如何在提交后有一个自动更新的下拉菜单？

Question

Here is my drop-down form. I have searched and still do not understand how to have a selected drop-down value remain after the cart is updated. Maybe it is because of the PHP in the name value? I would greatly appreciate any help. I believe this has to be done with javascript, but again I am unsure.

<select id="quantity" name='.$cart[$x]['ASIN'].'>
<option value=1>1</option>;
<option value=2>2</option>;
<option value=3>3</option>;
</select></td>';

Thanks,

Eric

Answer 1

As I understand it, you want the selected item to remain selected after the form is submitted and the page is refreshed... in this case you will need to do something like this:

<select name='mySelect'>
    <option value=1 <?=(isset($_POST['mySelect'])&&$_POST['mySelect']==1?'selected':'')?>>1</option>

Basically for each option you need to check if that select has a value, and if that value matches the current option ... if so, echo 'selected' which will set that option to the current displayed choice.

Unless, you have a situation where you're on like a profile page or something, and you want the user to be able to see his current setting, and still be able to change it... then you would need to do something similar but replace $_POST['mySelect'] with the data from the database. So if you have an array of user data, $data, and one of those values is 'quantity' that corresponds with the select, then you would need:

<option value=1 <?=($data['quantity']==1?'selected':'')?>>1</option>