download counter

[William Starr Moake]

I'm trying to script a download counter that will display the total
number on the download page without server-side scripting.

Below is my very incomplete beginning. It returns no errors, but does
nothing:

<script language="JavaS cript">
function addClicks() {
total = "form1.valu e";
form1.value = (eval(total.val ue) + (1));
}
</script>

<form name="form1" method="get">
<p><input type="text" name="total" maxlength="4" size="4"> <br>
<input type="button" name="addition" value="Download "
onclick="addCli cks();" width="10"></p></form>

What am I doing wrong?

[mscir]

Re: download counter

William Starr Moake wrote:[color=blue]
> I'm trying to script a download counter that will display the total
> number on the download page without server-side scripting.
> Below is my very incomplete beginning. It returns no errors, but does
> nothing:
> <script language="JavaS cript">
> function addClicks() {
> total = "form1.valu e";
> form1.value = (eval(total.val ue) + (1));
> }
> </script>[/color]

I've read in this group that "language" is no longer recommended, and
eval should be avoided when possible. Also, you weren't changing the
value of the textbox but of the form, maybe try something like this:

<script language="JavaS cript">
function addClicks() {
var formtotal=docum ent.forms("form 1").total
formtotal.value = +formtotal.valu e + 1;
}
</script>

Mike

[Richard Cornford]

Re: download counter

mscir wrote:[color=blue]
> William Starr Moake wrote:[color=green]
>> I'm trying to script a download counter that will display the total
>> number on the download page without server-side scripting.
>> Below is my very incomplete beginning. It returns no errors, but does
>> nothing:
>> <script language="JavaS cript">
>> function addClicks() {
>> total = "form1.valu e";[/color][/color]

The identifier - total - is being used in a way that would access a
global variable (or create one if one does not already exist as appears
to be the case). Variables should never be given more scope than they
need (general programming principle) and in this case - total - looks
like it should be local to the function (declared as - var total).
[color=blue][color=green]
>> form1.value = (eval(total.val ue) + (1));[/color][/color]

As - total - has been assigned a string value, the resolution of the
property accessor - total.value - will internally type-convert - total -
into a corresponding String object and then read a - value - property
from that String object. The result will be - undefined - (as String
objects have no - value - property), and therefor not of string type.
The eval function returns non-string arguments unaltered, so passing it
an undefined value is pointless (as it will do nothing but return that
value), but it also demonstrates a failure to even comprehend the
purpose of the - eval - function. (not that - eval - has any role in
this operation anyway).
[color=blue][color=green]
>> }
>> </script>[/color]
>
> I've read in this group that "language" is no longer
> recommended, and eval should be avoided when possible.[/color]

You have got the stress the wrong way around, we say - eval - should
*only* be used when it is *necessary* (and that it is almost never
necessary). To say "avoided when possible" would imply that ignorance of
the alternatives would justify its use, while in reality it should only
be used when there is certainty that there are no alternatives.
[color=blue]
> Also, you weren't changing the
> value of the textbox but of the form, maybe try something like this:
>
> <script language="JavaS cript">[/color]
<snip>

It seems odd to point out that the language attribute is not recommended
(because it is deprecated, and redundant when the required type
attribute is used) and then use it (and particularly without a type
attribute).

<script type="text/javascript">
[color=blue]
> var formtotal=docum ent.forms("form 1").total[/color]
^ ^
Parenthesising arguments for the - forms - collection is an IE-ism that
is not supported in many other browsers. The form of the expression is a
bracket notation property accessor, so the brackets should be square.

Richard.

[mscir]

Re: download counter

Richard Cornford wrote:[color=blue]
> mscir wrote:[/color]
<snip>[color=blue][color=green]
>>I've read in this group that "language" is no longer
>>recommended , and eval should be avoided when possible.[/color]
>
> You have got the stress the wrong way around, we say - eval - should
> *only* be used when it is *necessary* (and that it is almost never
> necessary). To say "avoided when possible" would imply that ignorance of
> the alternatives would justify its use, while in reality it should only
> be used when there is certainty that there are no alternatives.
>
>[color=green]
>>Also, you weren't changing the
>>value of the textbox but of the form, maybe try something like this:
>><script language="JavaS cript">[/color]
>
> It seems odd to point out that the language attribute is not recommended
> (because it is deprecated, and redundant when the required type
> attribute is used) and then use it (and particularly without a type
> attribute).
>
> <script type="text/javascript">
>[color=green]
>> var formtotal=docum ent.forms("form 1").total[/color]
> ^ ^
> Parenthesising arguments for the - forms - collection is an IE-ism that
> is not supported in many other browsers. The form of the expression is a
> bracket notation property accessor, so the brackets should be square.[/color]

Thanks Richard,
Mike

[William Starr Moake]

Re: download counter

On Tue, 13 Apr 2004 23:16:47 -0700, mscir
<mscir@access4l ess.com.net.org .uk> wrote:
[color=blue]
>William Starr Moake wrote:[color=green]
>> I'm trying to script a download counter that will display the total
>> number on the download page without server-side scripting.
>> Below is my very incomplete beginning. It returns no errors, but does
>> nothing:
>> <script language="JavaS cript">
>> function addClicks() {
>> total = "form1.valu e";
>> form1.value = (eval(total.val ue) + (1));
>> }
>> </script>[/color]
>
>I've read in this group that "language" is no longer recommended, and
>eval should be avoided when possible. Also, you weren't changing the
>value of the textbox but of the form, maybe try something like this:
>
><script language="JavaS cript">
>function addClicks() {
> var formtotal=docum ent.forms("form 1").total
> formtotal.value = +formtotal.valu e + 1;
>}
></script>
>[/color]
Your script works and actually retains the total when the page is
refreshed. BUT when the page is closed and reopened the total goes
back to zero. I guess everyone else was right: you have to use
server-side scripting to store the current total so that it's
displayed for the next person who accesses the page.

Thanks anyway.

[mscir]

Re: download counter

William Starr Moake wrote:[color=blue]
> Your script works and actually retains the total when the page is
> refreshed. BUT when the page is closed and reopened the total goes
> back to zero. I guess everyone else was right: you have to use
> server-side scripting to store the current total so that it's
> displayed for the next person who accesses the page.[/color]

Right, I looked at the code without considering the real problem, sorry
for any wasted time.

Mike

[William Starr Moake]

Re: download counter

On Wed, 14 Apr 2004 21:07:43 -0700, mscir
<mscir@access4l ess.com.net.org .uk> wrote:
[color=blue]
>William Starr Moake wrote:[color=green]
>> Your script works and actually retains the total when the page is
>> refreshed. BUT when the page is closed and reopened the total goes
>> back to zero. I guess everyone else was right: you have to use
>> server-side scripting to store the current total so that it's
>> displayed for the next person who accesses the page.[/color]
>
>Right, I looked at the code without considering the real problem, sorry
>for any wasted time.
>[/color]
No waste. At least your script counted the download clicks. I learned
something.

[MasonC]

Re: download counter

On Wed, 14 Apr 2004 17:09:23 -1000, William Starr Moake <wsmoake@yahoo. com> wrote:
[color=blue]
>On Tue, 13 Apr 2004 23:16:47 -0700, mscir
><mscir@access4 less.com.net.or g.uk> wrote:
>[color=green]
>>William Starr Moake wrote:[color=darkred]
>>> I'm trying to script a download counter that will display the total
>>> number on the download page without server-side scripting.
>>> Below is my very incomplete beginning. It returns no errors, but does
>>> nothing:
>>> <script language="JavaS cript">
>>> function addClicks() {
>>> total = "form1.valu e";
>>> form1.value = (eval(total.val ue) + (1));
>>> }
>>> </script>[/color]
>>
>>I've read in this group that "language" is no longer recommended, and
>>eval should be avoided when possible. Also, you weren't changing the
>>value of the textbox but of the form, maybe try something like this:
>>
>><script language="JavaS cript">
>>function addClicks() {
>> var formtotal=docum ent.forms("form 1").total
>> formtotal.value = +formtotal.valu e + 1;
>>}
>></script>
>>[/color]
>Your script works and actually retains the total when the page is
>refreshed. BUT when the page is closed and reopened the total goes
>back to zero. I guess everyone else was right:[/color]

you have to use[color=blue]
>server-side scripting to store the current total so that it's
>displayed for the next person who accesses the page.[/color]

How about storing it in a cookie?

Mason C

[Grant Wagner]

Re: download counter

MasonC wrote:
[color=blue]
> On Wed, 14 Apr 2004 17:09:23 -1000, William Starr Moake <wsmoake@yahoo. com> wrote:
>[color=green]
> >On Tue, 13 Apr 2004 23:16:47 -0700, mscir
> ><mscir@access4 less.com.net.or g.uk> wrote:
> >[color=darkred]
> >>William Starr Moake wrote:
> >>> I'm trying to script a download counter that will display the total
> >>> number on the download page without server-side scripting.
> >>> Below is my very incomplete beginning. It returns no errors, but does
> >>> nothing:
> >>> <script language="JavaS cript">
> >>> function addClicks() {
> >>> total = "form1.valu e";
> >>> form1.value = (eval(total.val ue) + (1));
> >>> }
> >>> </script>
> >>
> >>I've read in this group that "language" is no longer recommended, and
> >>eval should be avoided when possible. Also, you weren't changing the
> >>value of the textbox but of the form, maybe try something like this:
> >>
> >><script language="JavaS cript">
> >>function addClicks() {
> >> var formtotal=docum ent.forms("form 1").total
> >> formtotal.value = +formtotal.valu e + 1;
> >>}
> >></script>
> >>[/color]
> >Your script works and actually retains the total when the page is
> >refreshed. BUT when the page is closed and reopened the total goes
> >back to zero. I guess everyone else was right:[/color]
>
> you have to use[color=green]
> >server-side scripting to store the current total so that it's
> >displayed for the next person who accesses the page.[/color]
>
> How about storing it in a cookie?
>
> Mason C[/color]

Storing the value in a cookie will allow you to retain information about how many
times that specific user clicked the button/link, it won't allow you to count the
total number of clicks done by everyone.

--
| Grant Wagner <gwagner@agrico reunited.com>

* Client-side Javascript and Netscape 4 DOM Reference available at:
*

http://devedge.netscape.com/library/manuals/2000/javascript/1.3/reference/frames.html

* Internet Explorer DOM Reference available at:
* http://msdn.microsoft.com/workshop/a...ence_entry.asp
* Netscape 6/7 DOM Reference available at:
* http://www.mozilla.org/docs/dom/domref/
* Tips for upgrading JavaScript for Netscape 7 / Mozilla
* http://www.mozilla.org/docs/web-deve...upgrade_2.html