How to get an object handle by Id properly in Javascript

[anonieko]

<script type="text/javascript">
<!--
var Login1_UserNameRequired = document.all ?
document.all["Login1_UserNameRequired"] :
document.getElementById("Login1_UserNameRequired");

if (Login1_UserNameRequired)
{
// etc etc
}

-->
</script>

 

[Laurent Bugnion]

Hi,

<script type="text/javascript">
<!--

var Login1_UserNameRequired = document.all ?
document.all["Login1_UserNameRequired"] :
document.getElementById("Login1_UserNameRequired");

This doesn't handle browser with neither document.all nor
document.getElementById (Netscape 4 comes to mind). Granted, Netscape 4
is obsolete, but so is document.all...

if (Login1_UserNameRequired)
{

Good practice. But what do you do it it's not defined? A good error
handling is the difference between a professional looking product and an
amateurish website.

// etc etc
}

-->
</script>

Greetings,
Laurent