如何重新启动或重新加载“回显”下拉列表？

Question

I need to reload this HTML dropdown list after some database details get changed. Any ideas?

Note: ddl_my_items.reload(); is not working.

Thanks in advance.

<?php
//populates the ddl of items
$items = $dal->get_items() or die(mysql_error());

echo "<select id='ddl_my_items'>";
echo "<option value=''></option>";
foreach ($items as $item){
echo "<option value='$item->item_name'>$item->item_name</option>";
}
echo "</select>";
?>

Answer 1

It's easiest if you include jQuery.

create a php file ajax.php that only echoes the dropdown list contents:

<?php
//populates the ddl of items
$items = $dal->get_items() or die(mysql_error());

echo "<option value=''></option>";
foreach ($items as $item){
    echo "<option value='$item->item_name'>$item->item_name</option>";
}

Then, use the following javascript code:

$.get('ajax.php', function(result) {
    $('#ddl_my_items').html(result);
}

The function $.get sends an AJAX request (which is simply a HTTP request whose response can be received in javascript). The anonymous function is called as soon as the contents have been received.

$('#ddl_my_items') returns a jQuery object of the select element, and its html allow you to alter the element's content by passing the html code you've just received by the ajax call.