How to convert pounds to kilograms using jQuery? - php

Question

I have a form that allows the user to enter a weight, in either pounds or kilograms.
I'd like to store all of the data in kilograms, and using jQuery, would like the form to convert the weight_value to kilograms and change the weight_units option to "kg".
1 pound = 0.45359237 kilograms
The function should round the weight_value to the nearest kilogram (no decimals).
Any help you could provide would be appreciated!
<label> Weight:</label>
<input type="text" id="weight_value" />
<select id="weight_unit" />
<option value="lbs">lbs</option>
<option value="kg">kg</option>
</select>

Answer 1

Try this
function KtoLbs(pK) {
var nearExact = pK/0.45359237;
var lbs = Math.floor(nearExact);
return {
pounds: lbs,
};
}
var imperial = KtoLbs(10);
alert("10 kg = " + imperial.pounds + " lbs " );

Answer 2

My solution is here: http://jsfiddle.net/mVNDk/
$('#weight_unit').change(function(){
var v = $('input').val();
if($('#weight_unit').val() == 'lbs') {
$('input').val(v * 0.4535923);
} else {
$('input').val(v / 0.4535923);
}
});

Answer 3

try this
$(document).ready( function() {
$("#weight_value").keyup(function(){
var weight = parseFloat($("#weight_value").val());
if($("#weight_unit").val()=='lbs'){
//lbs value;
weight = (weight/0.45359237);
}else{
}
$("#weight_value_kg").val(Math.round(weight*100)/100);
});
});
<label> Weight:</label>
<input type="text" id="weight_value" />
<select id="weight_unit" />
<option value="lbs">lbs</option>
<option value="kg">kg</option>
</select>
<label> value:in kg</label>
<input type="text" id="weight_value_kg" />

Answer 4

Here is a try:
var kg = 0.45359237
$(document).ready(function() {
$("#weight_unit").change(function() {
if ($(this).val() == "kg") {
$("#weight_value").val(Math.round( $("#weight_value").val()*kg))
} else {
$("#weight_value").val(Math.round( $("#weight_value").val()/kg))
}
});
});
See it live on: http://jsfiddle.net/zeByX/
[EDIT] With the Math.floor(), you can get some weird results by switching from kg to pounds (try with 12 pounds and switch).

Answer 5

here's some code
$("#weight_unit").change(function() {
var result = 0;
if($(this).val() == "kg") {
result = Math.round($("#weight_value").val() * 0.45359237);
alert( result + " kg");
}
else {
result = Math.round($("#weight_value").val() / 0.45359237);
alert( result + " lbs");
}
});
you should replace the alert() functions for something you want to do with it

Answer 6

Checkout this fiddle buddy.
<label for='weight'>Weight</label>
<input type='text' id='weight' />
<select id='units'>
<option value='p'>Pound</option>
<option value='k'>Killogram</optoin>
</select>
<input type='text' id='result' />
with this script:
var weight = $('#weight'),
units = $('#units'),
result = $('#result');
// 1 pound = 0.45359237 kilograms
$(function() {
units.change(function() {
if ($(this).val() == 'p') {
// Weight is in Pound
result.val(weight.val() * 0.45359237);
}
else {
// Wiehgt is in Killogram
result.val(weight.val() / 0.45359237);
}
});
});