jQuery set radio button

Question

Your selector looks for the descendant of a input:radio[name=cols] element that has the id of newcol (well the value of that variable).

Try this instead (since you're selecting by ID anyway):

$('#' + newcol).prop('checked',true);

Here is a demo: http://jsfiddle.net/jasper/n8CdM/1/

Also, as of jQuery 1.6 the perferred method of altering a property is .prop(): http://api.jquery.com/prop

I found the answer here:
https://web.archive.org/web/20160421163524/http://vijayt.com/Post/Set-RadioButton-value-using-jQuery

Basically, if you want to check one radio button, you MUST pass the value as an array:

$('input:radio[name=cols]').val(['Site']);
$('input:radio[name=rows]').val(['Site']);

In your selector you seem to be attempting to fetch some nested element of your radio button with a given id. If you want to check a radio button, you should select this radio button in the selector and not something else:

$('input:radio[name="cols"]').attr('checked', 'checked');

This assumes that you have the following radio button in your markup:

<input type="radio" name="cols" value="1" />

If your radio button had an id:

<input type="radio" name="cols" value="1" id="myradio" />

you could directly use an id selector:

$('#myradio').attr('checked', 'checked');

You can try the following code:

$("input[name=cols][value=" + value + "]").attr('checked', 'checked');

This will set the attribute checked for the radio columns and value as specified.

Why do you need 'input:radio[name=cols]'. Don't know your html, but assuming that ids are unique, you can simply do this.

$('#'+newcol).prop('checked', true);

Try this:

$("#" + newcol).attr("checked", "checked");

I've had issues with attr("checked", true), so I tend to use the above instead.

Also, if you have the ID then you don't need that other stuff for selection. An ID is unique.

Using .filter() also works, and is flexible for id, value, name:

$('input[name="cols"]').filter("[value='Site']").attr('checked', true);

(seen on this blog)