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example of code
<SCRIPT LANGUAGE="JavaScript">
<!--
ns4 = (document.layers)? true:false
ie4 = (document.all)? true:false
function init() {
if (ns4) block = document.blockDiv
if (ie4) block = blockDiv.style
}
//-->
</SCRIPT><BODY onLoad="init()">
<A HREF="javascript:alert(block.left)">left</A> -
<A HREF="javascript:alert(block.top)">top</A>
<DIV ID="blockDiv" STYLE="position:absolute; left:50px; top:100px; background-color:red; layer-background-color:red;">
</DIV>
</BODY>
Let say if you don't have <div id="blockDIV"> then it will give you javascript error. how to get rid of error by ignoring the javascript script?
<html>
<head>
<title>Untitled</title>
<script type="text/javascript">
window.onerror = echo;
function echo(err) {
if(err) {
alert("The following JavaScript error occured:\n\n" + err);
return true;
}
}
</script>
</head>
<body>
<a href="javascript:blah()">Error 1</a>
<a href="javascript:alert('test)">Error 2</a>
<a href="javascript:echo()">No error</a>
</body>
</html>
You can customize the echo function to do whatever you want... Silently do nothing (= just return true) if you want, or whatever :)
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN""http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<title>Untitled</title>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1">
<style type="text/css">
html,body{height:100%;}
</style>
<script type="text/javascript">
function ckId(){
if(document.getElementById("divOne"))alert(true);
if(!document.getElementById("divTwo"))alert(false);
if(document.getElementById("divThree"))alert("won't happen");
}
</script>
</head>
<body onclick="ckId();">
<div id="divOne"></div>
</body>
</html>
if(document.getElementById('myDiv')) {
...
}
This checks if the id is present and then does what you want. One caveat is that you need to run this after the page has loaded so that you are sure that all elements have been rendered.
HTH
You can also just check for the presence of the <div>:if(document.getElementById('myDiv')) {
...
}
Oh, duh! Don't I feel stupid now :)
Rambo Tribble and BlobFisk are obviously right on the spot! However, if you still want to catch the error (or multiple errors)... ;)
[edited by: DrDoc at 3:14 pm (utc) on June 15, 2004]
Here's a spin off question (this isn't my thread but I'll ask anyway): what if you want to check for the presence of an ID (or do any number of other things) in NS4 where getElementById is unavailable?
