ele.style.height has problems on ie8

ele.style.height actually obtains the inline attribute, that is, the HTML file, the style attribute written in the HTML tag, not the height attribute in css

<div class="ele" style="height:20px;">
    我是一个div
</div>style="height:20px;">
    i am a div
</div>

And to get css in css, you have to write

ele.offsetHeight;