(window == any_element) always return true in IE6?

F

Fan

test page:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//ZH-CN" "http://
www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;
charset=UTF-8">
<title></title>
</head>
<body>
<input type=button id=a onclick=checkme() value=clickme>
</body>
</html>
<script type="text/javascript"><!--
function checkme() {
var a = document.getElementById("a");
alert("window==a? "+(window==a)); //true
alert("a==window? "+(a==window)); //false
}
--></script>
is it a bug of IE?
 
D

David Golightly

test page:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//ZH-CN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;
charset=UTF-8">
<title></title>
</head>
<body>
<input type=button id=a onclick=checkme() value=clickme>
</body>
</html>
<script type="text/javascript"><!--
function checkme() {
var a = document.getElementById("a");
alert("window==a? "+(window==a)); //true
alert("a==window? "+(a==window)); //false
}
--></script>
is it a bug of IE?
Click to expand...

Disregarding for a minute the script tag you have outside your HTML
tag (invalid!), this does indeed seem to be true: JScript in IE6 & IE7
seems to have a non-transitive comparison operator. You can try it by
navigating to http://www.google.com on IE and copy/pasting the
following into your address bar:

javascript:var g=document.getElementById('lgpd');alert((window==g)+','+
(g==window));

Now *THAT* is some serious junk code.

-David
 
D

David Golightly

Disregarding for a minute the script tag you have outside your HTML
tag (invalid!), this does indeed seem to be true: JScript in IE6 & IE7
seems to have a non-transitive comparison operator. You can try it by
navigating tohttp://www.google.comon IE and copy/pasting the
following into your address bar:

javascript:var g=document.getElementById('lgpd');alert((window==g)+','+
(g==window));

Now *THAT* is some serious junk code.

-David
Click to expand...

not "non-transitive", "asymmetric". Apologies.
 
E

Evertjan.

David Golightly wrote on 30 aug 2007 in comp.lang.javascript:
Disregarding for a minute the script tag you have outside your HTML
tag (invalid!), this does indeed seem to be true: JScript in IE6 & IE7
seems to have a non-transitive comparison operator. You can try it by
navigating to http://www.google.com on IE and copy/pasting the
following into your address bar:

javascript:var g=document.getElementById('lgpd');alert((window==g)+','+
(g==window));

Now *THAT* is some serious junk code.
Click to expand...

Let's keep it simple and compare:

<body>
<script type='text/javascript'>
var g=document.body;
alert((window == g)+','+(g == window));
</script>

and:

<body>
<script type='text/javascript'>
var g=document.body;
alert((window === g)+','+(g === window));
</script>
 
D

David Golightly

David Golightly wrote on 30 aug 2007 in comp.lang.javascript:




Let's keep it simple and compare:

<body>
<script type='text/javascript'>
var g=document.body;
alert((window == g)+','+(g == window));
</script>

and:

<body>
<script type='text/javascript'>
var g=document.body;
alert((window === g)+','+(g === window));
</script>
Click to expand...

Whichever way you slice it, same result. How 'bout that: IE's
equality operator is apparently broken.

-David
 
T

Thomas 'PointedEars' Lahn

Fan said:
test page:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//ZH-CN" "http://
www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;
charset=UTF-8">
<title></title>
</head>
<body>
<input type=button id=a onclick=checkme() value=clickme>
</body>
</html>
<script type="text/javascript"><!--
function checkme() {
var a = document.getElementById("a");
alert("window==a? "+(window==a)); //true
alert("a==window? "+(a==window)); //false
}
--></script>
is it a bug of IE?
Click to expand...

Your code is completely invalid: http://validator.w3.org/

But know this: `window' is a reference to a host object. With host objects,
all bets are off per the ECMAScript language specification. And MS JScript
is an ECMAScript implementation.


PointedEars
 
D

dhtmlkitchen

David Golightly said the following on 8/30/2007 2:13 PM:



It isn't IE's equality operator, it is IE's resolution of the window
object. If it were the equality operator then the the alerts would be
the same for window==g and g==window and they aren't. That alone says it
isn't the operator but something else.
Click to expand...

More on IE and window.event, see Dean's comment on window being not
equal to window.

http://www.davidflanagan.com/blog/2007_03.html

Interesting post on attachEvent's event argument.
http://www.davidflanagan.com/blog/2006_10.html#000114

Why anybody would need to compare a variable to window eludes me though.
Click to expand...

IF you have a popup or iframe.

var win = iframe.contentWindow;

window is weird in IE.

Garrett
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Similar Threads

When draggable=false & draggable=true dont work ? 1
Script stops working when using variables to save time typing... 4
Uncaught ReferenceError: item is not defined at HTMLButtonElement.onclick in the: <button onclick="item.inserir()">Inserir dados</button> 1
IE shows false and Firefox shows true 3
About as basic "Newbie-Question" that you can get. 3
XHTML - how extend/create ELEMENT body in my DTD? 0
Multi select options in a menu 1
Align img inside nav tabs section 5

Members online

Total: 23 (members: 1, guests: 22)
Robots: 422

Forum statistics

Threads
473,770
Messages
2,569,584
Members
45,075
Latest member
MakersCBDBloodSupport

Latest Threads

Top