Drop-down menu based on the selection of radio button - php

Question

I have four radio buttons and I would like to get the drop-down menu based on the selected radio button. Is it best if I just write all those drop-downs ready and display them based on the selection or is there a way to do it with ajax (because the drop-down values are coming from database) ?
Here are the radio buttons:
<input type="radio" name="some" value="someValue1">
<input type="radio" name="some" value="someValue2">
<input type="radio" name="some" value="someValue3">
<input type="radio" name="some" value="someValue4">
Here is the drop-down:
<select name="reason">
<?php
$data = WorkReason::all();
foreach ($data as $d) {
?>
<option value="<?php echo $d->code; ?>"><?php echo $d->reason; ?></option>
<?php
}
?>
</select>
I am using php ActiveRecords to get the values from database.
So if anybody knows a good way of doing this I would appreciate some help.

Answer 1

Make the different drop down lists and add a php condition to check which radio button was clicked and display that list.
You can use an array to select the correct code for you.
$radio2select = array ("someValue1" => "<select>..." , "someValue2" => "...", "someValue3" => "..."); // you get the idea
echo $radio2select($_REQUEST['radio']) ;
The use of an array is a trick to avoid using a switch statement, and it works well when your drop down boxes have been precomputed.
Otherwise, make a function which build the drop down box:
function select_reasons($which){
<select name="reason">
<?php
$data = WorkReason::all(array('conditions' => array ( 'reason = ?' => $which)));
foreach ($data as $d) {
?>
<option value="<?php echo $d->code; ?>"><?php echo $d->reason; ?></option>
<?php
}
?>
</select>
}
then just pass the $_REQUEST[‘radio'] to generate the corresponding dropdown list.
Note that I don't know your database schema, but I think that it should get you started.
Also, this code will work either on a regular Get or Post, or could be embedded within an ajax roundtrip (this depends on the framework you are using).
Another advantage is that only the necessary html code get included in the page, compared to a CSS based solution.

Answer 2

Make the different drop down lists and add a php condition to check which radio button was clicked and display that list.
if (isset($_POST['checkbox1']) {
echo '<select>...'
} else if (isset($_POST['checkbox2']) {
echo '<select>...'
}

Answer 3

Just load all Dropdown menues and display the one the user chose earlier with CSS:
display:block
display:none