WebRef   Sitemap · Experts · Tools · Services · Newsletters · About

home / web / dev / menus / intro2

Another Way

Sr. Web Developer mediabistro.com US-NY-New York Post A Job | Post A Resume

Developer News Microsoft Shows Off Silverlight 4, IE9 Plans Metasploit Expands Vulnerability Test Framework HyperCard Reborn?

Universal Related Popup Menus

Another way to approach the code is to first fill a two-dimensional array and create the new options on the fly. This technique makes it easier to add new menu items, and also extend this technique to another dimension. Here's a stripped down version for download.

Related Select Lists

The menus work identically to the previous page, and degrade gracefully. The array creation code has gone 2-D and now pregenerates the menu array outside the relate function.

var catsIndex = -1;
var itemsIndex;

function newCat(){
	catsIndex++;
	a[catsIndex] = new Array();
	itemsIndex = 0;
}

function O(txt,url) {
	a[catsIndex][itemsIndex]=new myOptions(txt,url);
	itemsIndex++;
}

function myOptions(text,value){
	this.text = text;
	this.value = value;
}

// fill array

newCat();
O("3-D Animation","/3d/");
O("Design","/dlab/");
O("DHTML","/dhtml/");
O("E-Commerce","/ecommerce/mm/");
O("Graphics","/graphics/");
O("HTML","/html/");
O("JavaScript","/js/");

newCat();
O("Authoring","/authoring/");
...

Can You Relate?

The relate function, which changes the second menu based on the first menu's selection, has been stripped of the on the fly array creation and now uses the 2-D array we created above to change the second menu's options on the fly.

function relate(formName,elementNum,j) {
if(v){
var formNum = getFormNum(formName);
 if (formNum>=0) {
	formNum++; // reference next form, assume it follows in HTML
	with (document.forms[formNum].elements[elementNum]) {
		for(i=options.length-1;i>0;i--) options[i] = null; // null out in reverse order (bug workarnd)
		for(i=0;i<a[j].length;i++){
			options[i] = new Option(a[j][i].text,a[j][i].value); 
		}
		options[0].selected = true;
	}
 }
} else {
jmp(formName,elementNum);
}
}

The guts of the relate function remain the same with two changes. The second menu's options array are now filled on the fly with the new Option command referring to the text and value properties of the a[j][i] element of our 2-D array. The aln2=a.length kludge was also replaced by calculating the length of the selectedIndex element of the 2-D array a (the number of options to be overwritten on the second menu).

This technique of pregenerating our options array can be extended into another dimension to create three related menus.

The full redirect.cgi script is also available in text form.

Comments are welcome

Search:

WebMediaBrands Corporate Info

Legal Notices, Licensing, Permissions, Privacy Policy.
Advertise | Newsletters | Shopping | E-mail Offers | Freelance Jobs

Solutions

Whitepapers and eBooks

Microsoft Articles: Visual Studio 2010 Adobe Article: Adobe Helps PHP Developers Create Rich Internet Applications Microsoft Whitepaper: How Windows Server 2008 R2 Helps Optimize IT and Save You Money Adobe Article: Java Developers Finding a Home at Adobe Flex IBM Articles: A Smarter Business Needs Smarter Technology Intel Xeon Processor Increases Server Efficiency and Capabilities Intel Tech Brief: Automated Energy Efficiency for the Intelligent Enterprise Oracle Whitepapers - Innovation for IT Leaders Avaya Article: Communication-Enabled Mashups--Empowering Both Business Owners and IT

Internet.com eBook: IT Manager's Guide to Social Networking Internet.com eBook: Get Ready for Windows 7 Microsoft Article: Expression Web 3--New Features for PHP Developers Whitepapers: Manage Your Business Infrastracture with IBM Whitepaper: Maximize Your Storage Investment with HP Internet.com eBook: Becoming a Better Project Manager Microsoft Article: Stress Free and Efficient Designer/Developer Collaboration MORE WHITEPAPERS, EBOOKS, AND ARTICLES

Webcasts

Webcast: Connecting PHP to Microsoft Technologies Video: Microsoft Partner Program Benefits Video: Windows Azure Debugging Tips SAP BusinessObjects Webcast: Unlock the Power of Reporting with Crystal Reports

IBM Webcast: Speed Business Innovation with Reduced Cost and Risk Video: Deploy Applications on Windows Azure MORE WEBCASTS, PODCASTS, AND VIDEOS

Downloads and eKits

Download: Microsoft Visual Studio 2010 Beta 2 Downloads & Free Trials: Microsoft's New Efficiency Resource Center Get the Windows 7 SDK

Free Trial: Red Gate SQL Backup Pro 6 Iron Speed Designer Application Generator MORE DOWNLOADS, EKITS, AND FREE TRIALS

Tutorials and Demos

Internet.com Hot List: Get the Inside Scoop on the Hottest IT and Developer Products All About Botnets

MORE TUTORIALS, DEMOS AND STEP-BY-STEP GUIDES

The latest from WebReference.com Browse > Site Contents - - - - - Experts * 3D Animation * Design * DHTML * Graphics * HTML * JavaScript * Perl * XML - - - - - Web Resources * Authoring * Design * Internet * Multimedia * Programming * Promotion - - - - - Services * Interviews * Newsletters * Reviews * Search * Tools Rolling Out Your Own HTML Application Version Control · HTML 5: Client-side Storage · Working with Ajax Server Extensions Sitemap · Experts · Tools · Services · Email a Colleague · Contact FREE Newsletters >   The latest from internet.com Wi-Fi Product Watch, November 2009 · Chip Market Recovering From '08 Collapse · Low-Cost Tools to Kickstart Your New Business

Created: Mar. 9, 1997
Revised: July 22, 1999

URL: http://webreference.com/dev/menus/intro2.html