How to pass option values to a button - php

Question

I'm trying to store variables from select/option, and then access them from a button to send to a javascript function that would filter some divs on my page.
So far I have it sending the value to "filter()" when the value changes.
Here's my markup:
<select name="Area" onchange="filter(this)">
<option selected>Select</option>
<option value="Austin">Austin</option>
<option value="San Antonio">San Antonio</option>
<option value="Temple">Temple</option>
</select>
<select name="Number" onchange="filter(this)">
<option selected>Select</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
<a class="button">Submit</a>
but how do I store the values from all the options, and then send them
all at once to the function?
Edit: In other words, how do I store the value of each option, and only send to the function once they click submit?

Answer 1

If I got it right, without jQuery you may try this:
document.getElementById("button").onclick = function() {
var selects = document.body.getElementsByTagName("select");
var data = [];
for (var i = 0; i < selects.length; i++) {
data.push(selects[i].value);
}
destinyFunction(data);
};
Or you may use jQuery for the sake of simplicity:
$("#jbutton").on("click", function() {
var data = [];
$("select").each(function() {
data.push($(this).val());
});
destinyFunction(data);
});
Fiddle with those two examples here.

Answer 2

Give each of your selects an id attribute, like:
<select name="Number" onchange="filter(this)" id="Number">
...
Then you can get the value of each in javascript by:
var el = document.getElementById('Number');
var value = el.options[el.selectedIndex].value;
As a sidenote, using onchange in HTML markup to attach your event handling is not best practice. This article from quirksmode offers a good explanation of alternative solutions. However, there are major cross-browser considerations to be taken into account, which is why most people prefer to use a Javascript framework so that those are mostly mitigated.