<head>
<meta charset="utf-8">
</head>
<body>
<a href="#" onClick="return false;" >Click</a>
<a href="#" onClick="return true;" >Click</a>
<script>
var b=document.getElementsByTagName('a');
alert(/return false;/.test(b[0].getAttribute('onClick')));
alert(/return false;/.test(b[1].getAttribute('onClick')));
</script>
</body>