[jQuery] math with form fields
Okay here's my form for a BMI Calculator I'm making.
<form action="" id="bmiCalc" onsubmit="return false;">
<fieldset>
<legend>Your BMI</legend>
<ol>
<li><label for="height">Height</label>
<select id="feet" class="textfield">
<option value="4">4</option>
<option value="5">5</option>
<option value="6">6</option>
<option value="7">7</option>
</select> ft
<select id="inches" class="textfield">
<option value="0">0</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
<option value="6">6</option>
<option value="7">7</option>
<option value="8">8</option>
<option value="9">9</option>
<option value="10">10</option>
<option value="11">11</option>
<option value="12">12</option>
</select> in</li>
<li><label for="weight">Weight</label><input id="pounds"
type="text" class="textarea"></li>
<li><input id="subCalc" type="image" title="submit"
alt="submit" src="imgs/btn.gif" class="submit-btn" /></li>
</ol>
</fieldset>
</form>
My problem is that I don't know how to retreive a number value from
select items. Then the math part is pretty fuzzy too.
Here's where I am so far...am I on the right track?
$(function () {
$('#subCalc').bind('submit',function(event) {
var feet = $('#feet').val();
var inches = $('#inches').val() || 0;
var pounds = $('#pounds').val();, 10);
var totalInches = feet * 12 + inches;
var bmi = Math.round(pounds * 703 * 10 / totalInches /
totalInches) / 10;
});
})