eval(),onError(),fileUpload(),Math.random()

I'm pretty good @ JavaScript, but I was wondering if you could help me with a few things I haven't learned...
I need help, basically, in knowing how, why, and when to use eval(),onError,and fileUpload(). I was also wondering if you could get Math.random() to return values between 1 specified number and another, rather that 0 to a specified number.

Thanks!

eval() is perhaps one of the most useful methods in javascript, it takes the argument, and tries to convert it into a javascript object, or any representation. It can sometimes act in place of parseInt() when mixing strings with numbers, and is necessary for DHTML in NS4:

function doSomething(layername) {
eval("document."+layername+".visibility="hide"
}
If you didn't use eval(), NS4 usually kicks up an error. (Atleast in my experience.)


onerror can be used on two things:
window.onerror
You can suppress error messages, and you can take some arguments on a function and actually obtain the error info. With that, you could fill out a form and submit it to a server side script, to notify you for example.
<img src="bla.gif" onError="alert('Image couldn't load.')">
Once again, you could try the above mailing, or use a script I wrote for someone at the www.wsabstract.com help forums to replace tge image with a default one if it doesn't load.

As for fileUpload(), I never have seen it in javascript.

Math.random() is very flexible in that manner.

var min=10;
var range=5;
var number=(Math.random()*range)+10;

That will generate a random number from
10 to 15.

Hope that helps some.

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Just a small correction on my above post, you do not need eval() for DHTML in NS4. I was thinking of something else. But you can still use it in the same manner:
function disable(what) {
eval('document.THEFORMNAME.'+what+'.disabled=true)
}



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Jason&nbsp;&nbsp;&nbsp;&nbsp;Contact Me
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