4-21.txt

开发王代码 代码

<script type="text/javascript">
<!--
  var n1 = 7;
  var n2 = 0;
  try {
    if (n2 == 0) {
      throw new Error("0不能作为被除数。");
    }
    document.write(n1/n2);
  } catch (err) {
    document.write("出错：" + err.message);
  } finally {
    delete n1;
    delete n2;
    document.write("<br />完成操作。");
  }
-->
</script>