JavaScript and DHTML References

>>	JavaScript Tutorial for Programmers
>>	Universal JavaScript Rollovers
>>	Speeding Up Image Rollovers Post page-load, pre-loading rollover images.

The JavaScript rollover code (from the above article) located in the <head> section of the HTML, can also be adapted to pre-load the images for non-rollover graphical navigation links.
DO use the "slice and paste together with a table" method on larger images, so only the small (file size) navigation images are pre-loaded.

I sometimes also adapt the onMouseOver part of the rollover code, to make certain that every browser that supports the required JavaScript will "respect" pre-loading the navigation images. (Somewhere in the past, I've seen that needed.)

A <body> tag onLoad command can also be used to load large page images after the rest of the page has finished loading.

If several images need to be "post-loaded", then the below JavaScript program is useful.

>>	Nebula Internet Software: OSLoader Load large images after the webpage loads.
>>	A flying menu attack (Dynamic menus) . . . can wound your navigation.

See also: Website Coding Programs.

[

Top of Page] [Site Policies] [Site Map]

^TM
Monitor this Webpage

E-mail the Webmaster
Page Content Updated: January 24, 2003

JavaScript runs on the client computer, placing it fully under the control of the end-user, or the appropriate systems administrator. So with the (small) prospect of someone maliciously using JavaScript, to destroy data or cause a security breach, some individuals and (large) organizations will simply disable JavaScript. . . . Not to mention all those annoying pop-up ads also stop occurring when JavaScript is disabled.
Thus, JavaScript should only be used to enhance the functionality of a Webpage, where the page content and site navigation never outright depend on it. (Everything works without JavaScript, but some things may work better using JavaScript.)