同一行上的JavaScript速记数学用于定义CSS值

Question

What is the shorthand to assign a CSS style and add the pixels on the same line? The following doesn't work though it should be exceptionally clear what I'm trying to do:

header.style.top = (h + 100)+px;

Answer 1

px is not defined. I believe you are intending to concat a string. Observe the following...

header.style.top = (h + 100) + 'px';

JSFiddle Link - simplified demo

Answer 2

header.style.top = (h + 100) + 'px';

Answer 3

I believe you don't need to specify the px value. It defaults to pixels

checkout this question: Using Javascript to add width to a HTML element

As found here http://javascript.info/tutorial/styles-and-classes-getcomputedstyle they say to enclose the px in brackets 'px' . Like the above answers.