console 命令行工具 X clear

console

$("input[name='rr']").change(function(){
    console.log('val>',$(this).val().toString());
    $('.log').text($(this).val());
})

<input type="radio" name="rr" value='1' checked>1</input>

<input type="radio" name="rr" value='2' >2</input>

<div class="log">1</div>