WebCoder.com - Your home for JavaScript and Dynamic HTML on the Web.

Since its incarnation, browser compatibility has been an issue with JavaScript. This listing attempts to cover some of the bugs, missing features, and new features that JavaScript has endured since version 1.0.

You'll find two sections here: Features and Bugs. The first section documents browsers' support for most of JavaScript's features; the second section documents the bugs, inconsistencies, or oddities of JavaScript features on a browser by browser basis.

JavaScript Features

Nav 2 Nav 3 Nav 4 IE 3 IE 4

applets
access to java No Yes Yes Yes¹ Yes¹

areas
image maps No Yes Yes No Yes

Array
create arrays No Yes Yes Yes Yes

css
control css No No Yes² No Yes

cookie
browser's cookie Yes Yes Yes Yes^* Yes

Date
time/date Yes Yes Yes Yes Yes

event
xtra event info No No Yes³ No Yes³

external scripts
with src attr No Yes Yes No⁴ Yes

forms
general forms Yes⁵ Yes Yes Yes^*,5 Yes

frames
control frames Yes Yes Yes Yes Yes

history
page history Yes Yes Yes Yes* Yes

images
control images No Yes Yes No⁹ Yes

javaEnabled
detect java No Yes Yes No Yes

links
control links Yes Yes Yes Yes Yes

location
control location Yes⁶ Yes Yes Yes^{*, 6} Yes

Math
math operations Yes Yes Yes Yes Yes

navigator
browser info Yes Yes Yes Yes Yes

mimeTypes
mime types No Yes Yes No No

options
control select
menu options No Yes Yes No No

String
create strings Yes Yes Yes Yes Yes

window
control window Yes^7,8 Yes⁸ Yes Yes^*,7,8 Yes⁸

write
write html Yes^* Yes^* Yes Yes Yes

JavaScript Bugs

Bug Description

IE 4
Still in "preview release"

IE 3
Cookies
Though IE 3 allows JavaScript access to cookies, the feature is disabled offline. So to work with cookies and JavaScript in IE 3, put your files on a server first.
Form's Action
You cannot change ACTION property of a form in IE 3 through JavaScript.
Form's Target
You cannot change TARGET property of a form in IE 3 through JavaScript.
Frames
While Navigator 2 bases the path of a frame's location on the URL of the frame that contains the controlling script, IE 3 bases the path on the URL of the target frame. For example, in Navigator 2, parent.B.location = "index.html" in frame A will result in frame B loading "index.html" in frame A's directory. Doing the same in IE 3 results in frame B loading "index.html" in frame B's directory.
Location
There are a few oddities with the location property in IE 3.0. First, using the javascript: protocol to go to a URL with location will result in nothing; the location of the window will not change. This is fixed in IE 3.01. Second, sometimes location cannot be accessed properly, so location.href should be used at all times.
Referrer
If the user gets to a page by following a link, the page's document.referrer property will return the url of the page that linked to it. In IE 3, the current page is always returned.
Windows
IE 3 has a few bugs dealing with windows. When you open a window using the open() method, the first parameter (for the url of the new window's document) will be ignored. Because of this, you must assign the location afterwards. Another bug deals with the opener property. When you open a new window, the new window is given a property, opener, which points to the window that opened it. There is no opener propery in IE 3.0. Both of these problems are fixed in IE 3.01.

Nav 4
CSS
There are a few problems with Navigator 4's CSS implementation (in relation to JavaScript). First, when you attempt to write to the DIV tags that surround an absolutetly positioned element, you will not recieve an error, but the content of the element will be cleared. Second, in complex layering situations the hidden and visible values for the visibility property will not work, and you will have to revert to the LAYER tag's hide and show values.

Nav 3
Tables
Navigator 3 has problems displaying JavaScript generated HTML (made with document.write()) inside tables. If you create a nested table (a table within a table) and try to put JavaScript generated HTML within it, either your code will be displayed or nothing will be displayed. Second, if you put certain JavaScript generated form elements within tables and then resize the window, the code will be displayed on the page and the table will "splurge" its contents.

^*implementation buggy or incomplete, see bugs table
¹access to ActiveX too, but no java api calls
²Nav only allows pre-display control, except with positioning
³the event model is improved, but it's different in IE and Nav
⁴external scripts supported in IE 3.01, but not 3.0
⁵no support for reset()
⁶no support for replace()
⁷no support for scroll(), focus(), blur()
⁸no support for moveTo(), moveBy(), resizeTo(), resizeBy()
⁹IE 3 for the Mac supports the image object

Code:

Questions:

garciagirljm@hotmail.com asks:
hello. i need to have 6 input fields, in one row. Next to that row will be an add button. underneath that row i need to have a table dynamically generated by that data. The rows in the table must have the option to be deleted, instead of added.

Comments:

JavaScript Features
	Nav 2	Nav 3	Nav 4	IE 3	IE 4
applets access to java	No	Yes	Yes	Yes¹	Yes¹
areas image maps	No	Yes	Yes	No	Yes
Array create arrays	No	Yes	Yes	Yes	Yes
css control css	No	No	Yes²	No	Yes
cookie browser's cookie	Yes	Yes	Yes	Yes^*	Yes
Date time/date	Yes	Yes	Yes	Yes	Yes
event xtra event info	No	No	Yes³	No	Yes³
external scripts with src attr	No	Yes	Yes	No⁴	Yes
forms general forms	Yes⁵	Yes	Yes	Yes^*,5	Yes
frames control frames	Yes	Yes	Yes	Yes	Yes
history page history	Yes	Yes	Yes	Yes*	Yes
images control images	No	Yes	Yes	No⁹	Yes
javaEnabled detect java	No	Yes	Yes	No	Yes
links control links	Yes	Yes	Yes	Yes	Yes
location control location	Yes⁶	Yes	Yes	Yes^{*, 6}	Yes
Math math operations	Yes	Yes	Yes	Yes	Yes
navigator browser info	Yes	Yes	Yes	Yes	Yes
mimeTypes mime types	No	Yes	Yes	No	No
options control select menu options	No	Yes	Yes	No	No
String create strings	Yes	Yes	Yes	Yes	Yes
window control window	Yes^7,8	Yes⁸	Yes	Yes^*,7,8	Yes⁸
write write html	Yes^*	Yes^*	Yes	Yes	Yes

JavaScript Bugs
	Bug Description
IE 4	Still in "preview release"

IE 3	Cookies Though IE 3 allows JavaScript access to cookies, the feature is disabled offline. So to work with cookies and JavaScript in IE 3, put your files on a server first. Form's Action You cannot change ACTION property of a form in IE 3 through JavaScript. Form's Target You cannot change TARGET property of a form in IE 3 through JavaScript. Frames While Navigator 2 bases the path of a frame's location on the URL of the frame that contains the controlling script, IE 3 bases the path on the URL of the target frame. For example, in Navigator 2, parent.B.location = "index.html" in frame A will result in frame B loading "index.html" in frame A's directory. Doing the same in IE 3 results in frame B loading "index.html" in frame B's directory. Location There are a few oddities with the location property in IE 3.0. First, using the javascript: protocol to go to a URL with location will result in nothing; the location of the window will not change. This is fixed in IE 3.01. Second, sometimes location cannot be accessed properly, so location.href should be used at all times. Referrer If the user gets to a page by following a link, the page's document.referrer property will return the url of the page that linked to it. In IE 3, the current page is always returned. Windows IE 3 has a few bugs dealing with windows. When you open a window using the open() method, the first parameter (for the url of the new window's document) will be ignored. Because of this, you must assign the location afterwards. Another bug deals with the opener property. When you open a new window, the new window is given a property, opener, which points to the window that opened it. There is no opener propery in IE 3.0. Both of these problems are fixed in IE 3.01.

Nav 4	CSS There are a few problems with Navigator 4's CSS implementation (in relation to JavaScript). First, when you attempt to write to the DIV tags that surround an absolutetly positioned element, you will not recieve an error, but the content of the element will be cleared. Second, in complex layering situations the hidden and visible values for the visibility property will not work, and you will have to revert to the LAYER tag's hide and show values.

Nav 3	Tables Navigator 3 has problems displaying JavaScript generated HTML (made with document.write()) inside tables. If you create a nested table (a table within a table) and try to put JavaScript generated HTML within it, either your code will be displayed or nothing will be displayed. Second, if you put certain JavaScript generated form elements within tables and then resize the window, the code will be displayed on the page and the table will "splurge" its contents.