<h3>iframe 中始终显示滚动条:</h3>
<iframe src ="/example/html/frame_scroll.html" width="200" height="200" scrolling="yes">
<p>Your browser does not support iframes.</p>
<h3>iframe 中从不显示滚动条:</h3>
<iframe src ="/example/html/frame_scroll.html" width="200" height="200" scrolling="no">
<p>Your browser does not support iframes.</p>