我可以将offsetHeight分配给style.top吗？

Question

In javascript, can I assign like this:

var tempHeight = document.getElementById("header").offsetHeight;
document.getElementById("content").style.top = tempHeight;

After running above script, will the div "content" have "top" propery = tempHeight? I tried but it does not work, any suggestions? Thanks!

Answer 1

你只需要一个单位

document.getElementById("content").style.top = String(tempHeight) + "px";

Answer 2

The top CSS property expects a unit along with the value. Adding px should work:

document.getElementById("content").style.top = tempHeight + "px";

Answer 3

You have to add + 'px' or some unit to the end of the style.top statement.

Also, #content must have the position style set

http://jsfiddle.net/BshuC/

CSS

 #header {
        height: 200px;
 }
 #content { position: absolute; }

JS

var tempHeight = document.getElementById("header").offsetHeight;
document.getElementById("content").style.top = tempHeight + 'px';