例子：
<script> var div=document.getElementById(div); var ho=div.offsetHeight; var hc=div.clientHeight; console.log(ho,hc);
1.offsetWidth
![这里写图片描述](https://www.cppentry.com/upload_files/article/49/1_147p3__.png "\")
offsetWidth=border+padding+height;
这里等于: 50+50+200+50+50=400<http://www.2cto.com/kf/ware/vc/" target="_blank" class="keylink">vcD4NCjxibG9ja3F1b3RlPg0KCTxwPtei0uKjujxzdHJvbmc+b2Zmc2V0V2lkdGg8L3N0cm9uZz6yu8Tc1NpkaXNwbGF5o7pub25ltcRkaXa78bXD1f3It9a1LL/J0tTTw2pxdWVyebXEPHN0cm9uZz5vdXRlcldpZHRoKCk8L3N0cm9uZz7V/ci3u/G1wzwvcD4NCjwvYmxvY2txdW90ZT4NCjxoMiBpZD0="2clientwidth">2.clientWidth
![这里写图片描述](https://www.cppentry.com/upload_files/article/49/1_pfg2a__.png "\")
clientWidth=padding+height-滚动条
这里等于：50+200+50-17=283
注意：jquery的innerWidth()可不把滚动条计算进去，可得到结果300
![这里写图片描述](https://www.cppentry.com/upload_files/article/49/1_nfgkd__.png "\")
scrollWidth=padding+包含内容的完全高度
这里等于：50+402+50=502
定义：获取位于元素顶部边界与元素中当前可见内容的最顶端之间的距离
scrollTop=scrollHeight-clientHeight
=padding+包含内容的完全高度-(padding+height-滚动条)
=包含内容的完全高度-height-滚动条