This sample demonstrates the use of the scrollWidth property to retrieve
the width of the viewable content.
The scrollWidth property is read-only, allowing you to obtain the
actual height of the viewable content. Even though the width of this
div is 400px, the width inside the scrolling text box might be less, since
the wrapped text may not use the entire area within the object. The scrollWidth
dimension can be useful for a variety of reasons; for example, the width
of the div could be set to the scrollWidth to conserve vertical
space while respecting the set height as a maximum.
[Right-click and choose View Source from the shortcut
menu.]