Checking for blank data

[Jerim79]

I am working on form validation. I have a scheme that is working for
me, except for 3 input fields. Zip, Phone, and Fax are the input
fields. I want to do two tests. First I want to check to make sure
there is data actually in the box. Next, I want to make sure that data
is only numbers.

The scheme I am using is:

$Zip=stripslashes($_POST["Zip"]);

function check_zip($Zip)
{
if(!preg_match("/[^0-9]+$/ ",$Zip))
return TRUE;
else
return FALSE;
}

if(!check_zip($Zip))
{
$msg7="Please input a valid 5 digit zip code. (No letters or special
characters.)";
$error++;
}

if ($Zip="")
{
$msg7="Please input a valid 5 digit zip code. (No letters or special
characters.)";
$error++;
}

Granted, I just read up on pregmatch today so it is new to me. The
problem I am having is that it doesn't report that the box is empty. If
I type letters into the box, it returns the error message, asking for a
valid 5 digit zip code. So the first IF seems to be working. If I put
the second IF in front of the first (rearrange them) it still doesn't
work. I thought "" was the basic way to check for NULL data across most
languages. I tried looking it up on the PHP website but didn't find
anything to indicate a different syntax. I tried doing an IF/ELSE but
that didn't work either. Any help is appreciated.

[Jerim79]

Jerim79 wrote:

I am working on form validation. I have a scheme that is working for
me, except for 3 input fields. Zip, Phone, and Fax are the input
fields. I want to do two tests. First I want to check to make sure
there is data actually in the box. Next, I want to make sure that data
is only numbers.

The scheme I am using is:

$Zip=stripslashes($_POST["Zip"]);

function check_zip($Zip)
{
if(!preg_match("/[^0-9]+$/ ",$Zip))
return TRUE;
else
return FALSE;
}

if(!check_zip($Zip))
{
$msg7="Please input a valid 5 digit zip code. (No letters or special
characters.)";
$error++;
}

if ($Zip="")
{
$msg7="Please input a valid 5 digit zip code. (No letters or special
characters.)";
$error++;
}

Granted, I just read up on pregmatch today so it is new to me. The
problem I am having is that it doesn't report that the box is empty. If
I type letters into the box, it returns the error message, asking for a
valid 5 digit zip code. So the first IF seems to be working. If I put
the second IF in front of the first (rearrange them) it still doesn't
work. I thought "" was the basic way to check for NULL data across most
languages. I tried looking it up on the PHP website but didn't find
anything to indicate a different syntax. I tried doing an IF/ELSE but
that didn't work either. Any help is appreciated.

Forgot to mention that I know you don't have to have two IF statements.
The first IF should return an error when it doesn't find numbers. But
that wasnt' working either.

[SquishedOrange]

Is empty() what your looking for.

You could also achieve it using strlen(), but empty is better.

[SquishedOrange]

function check_zip($Zip)
{
if(preg_match("/^[0-9]+$/ ",$Zip))
return TRUE;
else
return FALSE;

}
Also:
if(true == false){
echo("php is broken");
}

Note "==" instead of "=".

I reccomend reading this:
http://uk2.php.net/manual/en/language.operators.php

Hope this helps!
William

[SquishedOrange]

Untested!!!

$Zip=stripslashes($_POST["Zip"]);

if (empty($Zip)) {
$msg7="Please input a 5 digit zip code)";
$error++;
}

if(!preg_match("/^[0-9]+$/ ",$Zip)){
$msg7="Please input a valid 5 digit zip code. (No letters or special
characters.)";
$error++;
}

:)

[Jerim79]

SquishedOrange wrote:

Untested!!!

$Zip=stripslashes($_POST["Zip"]);

if (empty($Zip)) {
$msg7="Please input a 5 digit zip code)";
$error++;
}

if(!preg_match("/^[0-9]+$/ ",$Zip)){
$msg7="Please input a valid 5 digit zip code. (No letters or special
characters.)";
$error++;
}

:)

Shortly after posting this I was able to find empty. It works like a
charm. Thanks.

[SquishedOrange]

Jerim79 wrote:

SquishedOrange wrote:

Untested!!!

$Zip=stripslashes($_POST["Zip"]);

if (empty($Zip)) {
$msg7="Please input a 5 digit zip code)";
$error++;
}

if(!preg_match("/^[0-9]+$/ ",$Zip)){
$msg7="Please input a valid 5 digit zip code. (No letters or special
characters.)";
$error++;
}

:)

Shortly after posting this I was able to find empty. It works like a
charm. Thanks.

No problem. Note the change to your regular expression in the
preg_match line though.
Your old one won't work exactly as you intended and will match strings
that are only letters. Only by using a couple of "!" did it appear to
work correctly.

[Michael Fesser]

..oO(Jerim79)

>$Zip=stripslashes($_POST["Zip"]);

Why do you use this?

Micha

[Christoph Burschka]

Jerim79 schrieb:

if ($Zip="")

Firstly, you need == there. The way it's now, the if statement will
/set/ $zip to "".

Secondly, PHP has "weak types". This means that any variable can be used
like a string, a number or a boolean, etc.

Therefore, this works:

if (!$zip) {
echo "zip is either '', 0, false or not set at all.";
}

Note that if PHP is set to display "notice"-level errors, it will
generate a warning if $zip was never set. You can avoid this by first
checking if $zip was ever defined:

if (!isset($zip) || !$zip) {
echo "zip is missing";
}

--
CB

[Jerim79]

Michael Fesser wrote:

.oO(Jerim79)

$Zip=stripslashes($_POST["Zip"]);

Why do you use this?

Micha

stripslashes() strips the any spaces off the input either from the
beginning or ending of the text. It is good for formatting reasons.

[Michael Fesser]

..oO(Jerim79)

>stripslashes() strips the any spaces off the input either from the
beginning or ending of the text. It is good for formatting reasons.

That's not what stripslashes() does. You're looking for trim().

Micha