finally语句使您可以在try和catch之后执行代码，而不管结果如何。下面的示例将给出finally块的结果，即使catch块出现了错误。
<html>
<body>
<pre>
<script>
function addition() {
document.writeln("every one should be good at addition");
}
function substraction(){
document.writeln("substraction helps you");
}
try {
addition() division() }
catch(err) {
document.writeln("be good at division : " + err);
}
finally {
substraction() }
</script>
</pre>
</body>
</html>every one should be good at addition be good at division : ReferenceError: division is not defined substraction helps you