其他

a vs button

1. button 无法使用右键
2. a 有利于 搜索引擎

取消文本双击复制

<b onmousedown="return false"> some txt</b>

防止复制

<div oncopy="alert('Copying forbidden!');return false">
  Dear user, The copying is forbidden for you. If you know JS or HTML, then you
  can get everything from the page source though.
</div>