Cross-browser code needed

Does anyone have any sample code for what I'm trying to do? I need a way to prevent a user from clicking on a button (or image, preferably) twice. The button will load a 2nd page, but will either popup an alert or change its state to prevent from calling the next page again.

Here's what I've already tried:

var numberofclicks = 0;
function ClickTwice(URLLink)
{
if (numberofclicks == 0)
{
numberofclicks++;
document.URL = URLLink;
}
else
{
alert("You may only add one line item at a time. Please wait.");
}
}


The first time a user clicks, document.URL replaces the URL with whatever is passed in via a string. It increments a counter, and if that counter isn't zero, it pops up an alert.

The problem is that Netscape won't support an onClick from an image:

<img src="../images/addline.gif" onClick="ClickTwice('Admin_OrderAddLine.asp?transid=<%=strTransID%>&ordernumber=<%=strOrderNumber%>')" border="0">

This works in IE beautifully. Someone suggested I wrap this up in an HREF like this:

<a href="javascript:ClickTwice('Admin_OrderAddLine.asp?transid=<%=strTransID%>&ordernumber=<%=strOrderNumber%>')"><img src="../images/addline.gif" border="0"></a>

However, this won't work in IE. When I click once in IE, it starts loading the 2nd page, and if I click twice, it pops up the alert. BUT, when I click to close the alert box, IE stops going to the next page. (presumably because I clicked on an HREF, so it cancelled the first HREF request)

ARGH! There seems to be no way to do it this way with IE and Netscape. Is there another way? I tried messing around with the visibility of the object - but that only works in IE. I can't make the button disappear in Netscape.

Thanks guys.
- Jeff
Dallas, TX

This is of the top of my head so I don't know whether it will make any difference but have you tried this:

<a href="#" onClick="ClickTwice('Admin_OrderAddLine.asp?transid=<%=strTransID%>&ordernumber=<%=strOrderNumber%>')"><img src="../images/addline.gif" border="0"></a>

ie. use a dummy link and retain the onClick event.

John

I've tried to do something similar before and all I could come up with was to put the URL change after the alert message aswell. It means that it's going to start the page request all over again but the extra wait shouldn't be too long and that's what they get for being impatient anyway