This is really a question for JavascriptMonks, but I'll chime in to say jQuery makes fiddling with things like checkboxes a lot easier, and you don't have to plug those ugly onClick things into your HTML: 

<head>
    <script type="text/javascript"
        src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery
+.min.js"></script>
    <script type="text/javascript">
        $(document).ready(function(){
            $('input.g[name!="loner"]').click(function(e){
                $('input.g[name="loner"]').prop('checked',false);
            });
            $('input.g[name="loner"]').click(function(e){
                $('input.g[name!="loner"]').prop('checked',false);
            });
        });
    </script>
</head>
<body>
    <form>
        <input type=checkbox name=loner class=g />Loner
        <input type=checkbox name=a class=g />A
        <input type=checkbox name=b class=g />B
        <input type=checkbox name=c class=g />C
        <input type=checkbox name=d class=g />D
    </form>
</body>

[download]

Aaron B.
Available for small or large Perl jobs; see my home node.

In reply to Re: How to uncheck one checkbox if some other is checked by aaron_baugher
in thread How to uncheck one checkbox if some other is checked by SerZKO

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.