Hi,
I have had to invent a work-around to get past what looks like a
JavaScript bug, the malfunctioning Perl-like JavaScript array functions
including SPLICE() and UNSHIFT().
I have boiled it down to a very simple test case which can be
cut-n-pasted into a .html file and viewed in a browser:
================================================== ==========================
<META HTTP-EQUIV="expires" VALUE="Tue, 23 Jun 1998 01:46:05
GMT"><!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en-US"
xml:lang="en-US">
<head>
<title>Weird JavaScript Array Function Malfunction!</title>
<meta name="expires" content="Tue, 23 Jun 1998 01:46:05 GMT" />
<script type="text/javascript">//<![CDATA[
function resort() {
var sortara = new Array;
sortara = document.aceform.sort.options;
var length = sortara.length;
alert("SortAra length = " + sortara.length)
var selidx = document.aceform.sort.selectedIndex;
alert("Selected Index = " + selidx);
var selected = sortara[selidx];
alert("Selected item = " + selected.text);
selected = sortara.splice(selidx, 1); // Remove selected array item.
alert("Selected item = " + selected.text); // Never gets here.
Error.
sortara.unshift(selected); // Insert item at top of array.
}
//]]></script>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"
/>
</head>
<body bgcolor="#B0CEBE">
<form method="post" action="" enctype="multipart/form-data"
name="aceform">
<center>
<table border="2" cellspacing="2" cellpadding="2">
<tr><td><center>Sort</td></tr>
<tr><td align="center">
<select name="sort" size="4" onchange="resort(this)">
<option value="Item1">Item1</option>
<option value="Item2">Item2</option>
<option value="Item3">Item3</option>
<option value="Item4">Item4</option>
</select></td>
</tr>
</table>
</center><div></div></form>
</body>
</html>
================================================== =======================
The intent of this script is to move the selected item to the to of the
menu. What could be simpler? Something similar to the Perl one-liner:
unshift(@array, splice(@array, $selectIndex, 1)); # Move SelIdx item
to top.
In a JavaScript console in Firefox 1.0.6 as well as in Opera and
evilnet explorer, I get the error message, "Error: sortara.splice is
not a function". Sortara is valued with
"document.aceform.sort.options", and options is an array.
The first 3 alerts show exactly what they should. The array length
comes out to 4, the selected item shows 3 if I click on the last item,
and the item description matches my selection, "Item3" if I choose the
last one. The final alert is never reached, but instead the JavaScript
terminates and a new error message (above) is written to the JS
console.
The 'Reilly Rhino book, "JavaScript, The Definitive Guide" documents
the select object's OPTIONS property as, "An ARRAY of option objects
...."
I can only find 3 hits on this in Google. Is this a real JavaScript bug
or am I loosing it?
THX,
BrianP
