Valeur d'un bouton radio

by ydelmas

HTML

<span id="groupe">
    <input type="radio" name="a" value="1" />
    <input type="radio" name="a" value="2" />
</span>
<button type="button" onclick="test()">test</button>
<div id="msg">&nbsp;</div>

JavaScript

function message(s) {
    document.getElementById('msg').innerHTML=s;
}
function test() {
    var r = document
                .getElementById('groupe')
                .querySelector(':checked');
    if ( r == null ) {
        message("rien n'est coché");
    } else {
        message('valeur : '+ r.value);
    }
}