CPU 100% on a Loop while retrieving form values

[Kant]

Hi,

i have a simple problem. i have a form with a lot's of number of Text
and Hidden Fields. I just do a simple loop to get each value for each
attribute. I have about more than 2000.

if i do something simple like :

for (var i=0; i<2000; i++)
aValue = i+10;

it runs well. But if i do something like
for (var i=0; i<2000; i++)
aValue = document.myForm .elements[i].value;

it gives me 100% CPU for a long time before i submit the form.

Cheers,

Kant.

[Richard Cornford]

Re: CPU 100% on a Loop while retrieving form values

"Kant" <kanthann@hotma il.com> wrote in message
news:7e58446c.0 401160730.59618 928@posting.goo gle.com...[color=blue]
>i have a simple problem. i have a form with a lot's of number
>of Text and Hidden Fields. I just do a simple loop to get each
>value for each attribute. I have about more than 2000.
>
>if i do something simple like :
>
>for (var i=0; i<2000; i++)
> aValue = i+10;
>
>it runs well. But if i do something like
>for (var i=0; i<2000; i++)
> aValue = document.myForm .elements[i].value;
>
>it gives me 100% CPU for a long time before i submit the form.[/color]

It is very inefficient to resolve document.myForm .elements 2000 times.
Compare it with:-

var els = document.forms['myForm'].elements;
for(var c = 0; c < 2000;c++){
aValue = els[c].value;
}

But looking up properties on 2000 object is going to be relatively slow
however you do it.

Richard.

[Lee]

Re: CPU 100% on a Loop while retrieving form values

Kant said:[color=blue]
>
>Hi,
>
>i have a simple problem. i have a form with a lot's of number of Text
>and Hidden Fields. I just do a simple loop to get each value for each
>attribute. I have about more than 2000.
>
>if i do something simple like :
>
>for (var i=0; i<2000; i++)
> aValue = i+10;
>
>it runs well. But if i do something like
>for (var i=0; i<2000; i++)
> aValue = document.myForm .elements[i].value;
>
>it gives me 100% CPU for a long time before i submit the form.[/color]

Move as much as possible to outside the loop:

var myElements=docu ment.myForm.ele ments;
for(var i=0;i<2000;i++) {
aValue=myElemen ts[i].value;
}

Slightly more efficient, but probably not practical in whatever
you're really doing:

var myElements=docu ment.myForm.ele ments;
for(var i=0;i<2000;aVal ue=myElements[i++].value);

[ZeBest Kant]

Re: CPU 100% on a Loop while retrieving form values

Ok thanks a lot guys :D

it works fine !!!

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