get selected index of checked radio button

[sourabhjha]

i have a requiresment where i have to get the index of the checked radio button on form load...and capture that number to recognise that element on some button click function on the form..anyhelp

 

[jemminger]

var el = document.forms[0].myRadioButtonName;

for (x = 0; x < el.length; x++)
if (el[x].checked)
return x;
=========================================================
if (!succeed) try();
-jeff

 

[sbanks]

You can modify this to suit your needs. &quot;radioObject&quot; is the radio button input. This script gets the value that's selected; so instead of proceeding to get the value, when it gets to the checked option you'd want to return i (try, value = i and change the return value line to read &quot;return i&quot;.

function getRadioValue(radioObject){
var value = null;
for (var i=0; i<radioObject.length; i++){
if (radioObject.checked){
value = radioObject.value;
break}
}
return value;
}

 

[jemminger]

oops - should wrap it in a function:
[tt]
function getIndex(o) {
for (x = 0; x < o.length; x++)
if (o[x].checked)
return x;
}

[/tt]
call it like so:[tt]
var n = getIndex(document.forms[0].myRadioName);[/tt] =========================================================
if (!succeed) try();
-jeff