What are the major differences one should keep in mind when trying to make a Web page/site compliant for both Internet Explorer 4+ and Netscape Communicator 4+?

Jayesh Nazre

Following are some of the guide lines which you can use.

1. Do not Use VBScript if you want to target both the browsers for client side validation.
2. The DHTML supported by both browsers is not the same e.g. innerHTML is a property available only in IE. Layers are available only in NS.
3. The event handling of IE/NS is also different
   IE has what I call bubbling event model (bubbling because the events bubble from the bottom to the top).
   NS has what I call drop down model (drop down because the events drop from top to bottom).
4. The properties of the event object and how the events are captured are also different.
5. Also certain features are available only in one browser. For example:
   a) "disabled" attribute associated with input tag with type=text is available only in IE.
   b) showModalDialog() function available in JavaScript (rather JScript) is also available only in IE.
6. Also note that Microsoft's version of JavaScript is JScript.
7. Also, if you are planing to use XML please note that only IE supports it, NS6.0 says they support it but I haven't tried. All earlier versions of NS do not support XML.
8. IE does not need a form tag to show any elements like say (a text field), NS needs a form tag. Without a form tag it will not show any elements.

Many people give different solutions for cross-browser issue. Broadly speaking they will fall in the foll. catagory:

• Do not use anything that is not supported by both the browsers (this is very tough to accept).
• Use two different function sets to handle cross brower issues.
• Use a single function set with a flag to identify which brower the script is running in. This you can easily find out by using the appVersion, appName properties of the navigator object.
• Another useful piece of advice, try to write code which works with NS browser, because if the code works in NS then almost 3/4 of your work is done, because coding in IE thanks to Microsoft is easier. Remember they are the ones who deviated from the W3C standards.

My suggestion to you is to use two different function sets for the browsers, this makes the coding much easier and simpler because you know for which browser you are coding.