Problem with 'switch' and zero

[Steve Loft]

I'm trying to use a switch construct to compare the result of a form
with a list of known values and display a different page according to
the submitted string. The problem is that some of the answers I need to
check for are strings of the character zero of varying length:

E.g.
<?php

switch (trim(strtolowe r($_POST['answer']))):

case "abc":
case "xyz":
case "0":
include 'close.htm';
break;
case "0000000000 ":
include 'vclose.htm';
break;
default:
include 'sorry.htm';
endswitch;
?>

What happens is that a submission consisting of a string of any number
of zeroes cause the first page to be displayed rather than the second. I
thought this was because it was treating it as an integer 0, so I tried
putting (string) casts all over the place, which didn't help.

Could someone please tell me how to achieve what I want?
--
Steve Loft

[Pedro Graca]

Re: Problem with 'switch' and zero

Steve Loft wrote:[color=blue]
> I'm trying to use a switch construct to compare the result of a form
> with a list of known values and display a different page according to
> the submitted string. The problem is that some of the answers I need to
> check for are strings of the character zero of varying length:[/color]
[color=blue]
> I thought this was because it was treating it as an integer 0, so I
> tried putting (string) casts all over the place, which didn't help.[/color]

No. PHP switch()s compare with "=="

and, for PHP
"000000" == "0"
is true.

You have to turn that switch into a series of if()s -- AFAIK there is no
way to do "000000" === "0" (which if false) inside the switch() construct

so, instead of
switch(somethin g):
case "abc":
...


do
if (something === "abc") ...
elseif (something === "0") ...
elseif (something === "000000") ...
...
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[Steve Loft]

Re: Problem with 'switch' and zero

Pedro Graca wrote:
[color=blue]
> You have to turn that switch into a series of if()s -- AFAIK there is no
> way to do "000000" === "0" (which if false) inside the switch() construct[/color]

Ah. OK, thanks very much, even if it wasn't good news. That seems pretty
stupid of PHP to me, but anyway...
--
Steve Loft

[Steve Loft]

Re: Problem with 'switch' and zero

Pedro Graca wrote:[color=blue]
>
> You have to turn that switch into a series of if()s -- AFAIK there is no
> way to do "000000" === "0" (which if false) inside the switch() construct[/color]

I've tried this, and I get the same result. I've even tried putting
string casts in, and I've tried single quotes and double quotes:

$ans = (string)trim(st rtolower($_POST['answer']));

if ((string)$ans == (string)"0") {
include 'close.htm';
} elseif ((string)$ans == (string)"000000 0000") {
include 'vclose.htm';
} else {
include 'sorry.htm';
}

If the form sends 0000000000, then the 'close.htm' file gets displayed.
This is my first attempt at writing PHP and it's driving me insane -
what am I doing wrong?
--
Steve Loft

[Steve Loft]

Re: Problem with 'switch' and zero

I wrote:
[color=blue]
> I've tried this, and I get the same result. I've even tried putting
> string casts in, and I've tried single quotes and double quotes:[/color]

Pedro,

Sorry. Sorry. Sorry. I didn't RTFM. I didn't realise what you meant when
you used the "===" comparison. I now have it working with if...elseif...
Thanks very much!
--
Steve Loft

[Pedro Graca]

Re: Problem with 'switch' and zero

Steve Loft wrote:[color=blue]
> I didn't realise what you meant when you used the "===" comparison.[/color]

I call that the "very equal" comparison
and similarly, the "!==" I call the "very different" comparison :)

so I read this
if ($a === false) whatever();

as "if a is very false" do whatever
[color=blue]
> I now have it working with if...elseif...
> Thanks very much![/color]

You're welcome
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[Geoff Berrow]

Re: Problem with 'switch' and zero

I noticed that Message-ID:
<c2pgs7$1vjaon$ 2@ID-203069.news.uni-berlin.de> from Pedro Graca
contained the following:
[color=blue][color=green]
>> I didn't realise what you meant when you used the "===" comparison.[/color]
>
>I call that the "very equal" comparison
>and similarly, the "!==" I call the "very different" comparison :)[/color]

Not "barely different"?

--
Geoff Berrow (put thecat out to email)
It's only Usenet, no one dies.
My opinions, not the committee's, mine.
Simple RFDs http://www.ckdog.co.uk/rfdmaker/

[CountScubula]

Re: Problem with 'switch' and zero

"Steve Loft" <steve@nybbles. co.uk> wrote in message
news:7lj4i1-kml.ln1@galena. nybbles.co.uk.. .[color=blue]
> I'm trying to use a switch construct to compare the result of a form
> with a list of known values and display a different page according to
> the submitted string. The problem is that some of the answers I need to
> check for are strings of the character zero of varying length:
>
> E.g.
> <?php
>
> switch (trim(strtolowe r($_POST['answer']))):
>
> case "abc":
> case "xyz":
> case "0":
> include 'close.htm';
> break;
> case "0000000000 ":
> include 'vclose.htm';
> break;
> default:
> include 'sorry.htm';
> endswitch;
> ?>
>
> What happens is that a submission consisting of a string of any number
> of zeroes cause the first page to be displayed rather than the second. I
> thought this was because it was treating it as an integer 0, so I tried
> putting (string) casts all over the place, which didn't help.
>
> Could someone please tell me how to achieve what I want?
> --
> Steve Loft[/color]

just a hunch, a bandaid if you will. I have this problem in vb apps with
keys, keys that start with numbers are not allowed in collections, so I
preface them.

switch "_" . (trim(strtolowe r($_POST['answer']))):
{
case "_0":

case "_000000000 0":
}

--
Mike Bradley
http://www.gzentools.com -- free online php tools