body.onunload event does not fire

shripaldalal · Jan 18, 2009

Hi,

this works:
<html><body onunload="alert('bye');"></body></html>

THIS DOES NOT WORK:
<html><head><script language=JavaScript>
document.body.onunload = saybye();
function saybye() { alert("bye"); }
</script></head><body></body></html>

document.body.onload = function() works but document.body.onunload =
function() does not work. Can someone throw more light on this ?
Thanks. Bye.

Regards,
Shripal.

Evertjan. · Jan 18, 2009

wrote on 18 jan 2009 in comp.lang.javascript:

Hi,

this works:
<html><body onunload="alert('bye');"></body></html>

THIS DOES NOT WORK:
<html><head>
<script language=JavaScript>

document.body.onunload = saybye();

That will load the result value of the executed saybye() in onunload,
and onunload will not know what to do with that.
Better link the saybye() function pointer to onunload with:

document.body.onunload = saybye;

[..]

RobG · Jan 18, 2009

Hi,

this works:
<html><body onunload="alert('bye');"></body></html>

THIS DOES NOT WORK:
<html><head><script language=JavaScript>
document.body.onunload = saybye();
function saybye() { alert("bye"); }
</script></head><body></body></html>

document.body.onload = function() works but document.body.onunload =
function() does not work. Can someone throw more light on this ?

Even if the inappropriate call operator is removed, your code, being
global code in the head element, may well be executed before the body
element exists. Even it isn't in some circumstances, it will be in
others.

Attach listeners to the body element at a point when you are sure that
it will exist. And even then, check that it does exist before
attempting to attach the listener.

dhtml · Jan 21, 2009

Evertjan. said:
wrote on 18 jan 2009 in comp.lang.javascript:

Hi,

this works:
<html><body onunload="alert('bye');"></body></html>

THIS DOES NOT WORK:
<html><head>
<script language=JavaScript>

document.body.onunload = saybye();

Click to expand...

That will load the result value of the executed saybye() in onunload,
and onunload will not know what to do with that.
Better link the saybye() function pointer to onunload with:

document.body.onunload = saybye;

[..]

Click to expand...

Which browser did you test that in?

The problem is that body.onunload is not the same thing as the content
attribute, <body onload="...".

The latter points to window.onload. The former augments the body element
with an |onunload| property.

We've discussed this here before.

Evertjan. · Jan 21, 2009

dhtml wrote on 21 jan 2009 in comp.lang.javascript:

document.body.onunload = saybye;

[..]

Click to expand...

Click to expand...

Which browser did you test that in?

The problem is that body.onunload is not the same thing as the content
attribute, <body onload="...".

The latter points to window.onload. The former augments the body element
with an |onunload| property.

Damn, you're right, used the headbrowser

dhtml · Jan 22, 2009

Evertjan. said:
dhtml wrote on 21 jan 2009 in comp.lang.javascript:

document.body.onunload = saybye;

[..]

Click to expand...

Which browser did you test that in?

The problem is that body.onunload is not the same thing as the content
attribute, <body onload="...".

The latter points to window.onload. The former augments the body element
with an |onunload| property.

Click to expand...

Damn, you're right, used the headbrowser

Me too

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body.onunload event does not fire

shripaldalal

Evertjan.

RobG

dhtml

Evertjan.

dhtml

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