On Apr 22, 10:22 pm, "Evertjan." <exjxw.hannivo...@interxnl.net>
wrote:
Peroli wrote on 22 apr 2008 in comp.lang.javascript:
function getSelectedValueForName(name) {
var inputs = document.getElementsByTagName("input");
for (var i = 0, len = inputs.length; i < len; i++) {
if (inputs[i].type == "radio" && input[i].checked) {
return input[i].value;
}
}
return null;
}
Where is the parameter called name used?
If the inputs have a common name in a form do:
var inputs = document.forms['myForm'].elements[name];
--
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)
Evertjan,
I agree. I will test my code before posting from now on.
Tim,
I agree to your first point that using inputs[i] 3 times is not
efficient.
In-fact, my test results showed that its slower by 10 - 30%.
I wrote a small test script and found that $$ is indeed faster in
Firefox and Safari.
Haven't tested it in IE, but I know it will be slower, because $$
uses native xpath.
Evaluate my test script and share your suggestions. I am open to
criticism.
--- Script (uses prototype.js) ---
<html>
<head>
<title>Benchmark</title>
</head>
<body>
<form id="test_form">
<input type="button" id="getValues" value="getValues">
</form>
<span id="result" />
<script type="text/javascript" src="http://prototypejs.org/assets/
2008/1/25/prototype-1.6.0.2.js"></script>
<script type="text/javascript">
function getSelectedValueForName(name) {
for (var i = 0; i <
document.getElementsByTagName(name).length; i++) {
var input = document.getElementsByTagName(name)[i];
if (input.type == "radio" && input.checked) {
return input.value;
}
}
return null;
}
function getSelectedValueForName1(name) {
var inputs = document.getElementsByTagName(name);
for (var i = 0, len = inputs.length; i < len; i++) {
if (inputs[i].type == "radio" && inputs[i].checked) {
return inputs[i].value;
}
}
return null;
}
function getSelectedValueForName2(name) {
var inputs = document.getElementsByTagName(name);
for (var i = 0, len = inputs.length; i < len; i++) {
var input = inputs[i];
if (input.type == "radio" && input.checked) {
return input.value;
}
}
return null;
}
function getSelectedRadioValue() {
return $$('input:checked[type="radio"]').pluck('value');
}
function benchmark() {
var d = new Date();
(100).times(
function() {
var vals = getSelectedValueForName('input');
}
);
var t1 = (new Date()) - d;
d = new Date();
(100).times(
function() {
var vals = getSelectedValueForName1('input');
}
);
var t2 = (new Date()) - d;
d = new Date();
(100).times(
function() {
var vals = getSelectedValueForName2('input');
}
);
var t3 = (new Date()) - d;
d = new Date();
(100).times(
function() {
var vals = getSelectedRadioValue();
}
);
var t4 = (new Date()) - d;
$('result').update( "Tim's way:" + t1 + '<br />caching1:' + t2 +
'<br />caching2:' + t3 + '<br /$$:' + t4);
}
function init() {
var frm = $('test_form');
(1000).times(
function (count) {
frm.insert({bottom:'<input type="radio" name="radio' +
count + '" value="value' + count + '" />'});
}
);
Event.observe('getValues', 'click', benchmark);
}
Event.observe(window, 'load', init);
</script>
</body>
</html>
-- Peroli Sivaprakasam
