Form validation

[Jerim79]

I am looking into form validation for my HTML form. I don't want to use
javascript and was looking into using PHP. A crazy thought crossed my
mind and I just wanted to get some input.

What if I basically made the form one long if/then statement? I could
ask for the first piece of information, test it against some
conditions, then if it is okay I allow the user to fill in the next
piece of information. I could go do down the page validation each box
as we go. I could use hidden on all the text boxes until the previous
condition had been validated. Some pseudocode:

<?php
<form action=POST method=register ed.php>
<input name"Fname" type="text">
if ($Fname meets some condition)
{
<input name="Lname" type="text">
if ($Lname meets some condition)
{
<input name="Number" type="text>
if ($Number meets some condition)
{
}
}
}
else;
echo "Please enter a phone number";
else;
echo "Please enter a valid last name";
else;
echo "Please enter a valid first name";
?>

I know the code isn't exact, I am just theorizing here. Could such a
thing be done? Even remotely similar? I don't really plan on doing this
anytime soon, but I was just curious. I only started PHP programming a
few days ago so no need to point out how stupid this may sound.

[Jerry Stuckle]

Re: Form validation

Jerim79 wrote:

I am looking into form validation for my HTML form. I don't want to use
javascript and was looking into using PHP. A crazy thought crossed my
mind and I just wanted to get some input.
>
What if I basically made the form one long if/then statement? I could
ask for the first piece of information, test it against some
conditions, then if it is okay I allow the user to fill in the next
piece of information. I could go do down the page validation each box
as we go. I could use hidden on all the text boxes until the previous
condition had been validated. Some pseudocode:
>
<?php
<form action=POST method=register ed.php>
<input name"Fname" type="text">
if ($Fname meets some condition)
{
<input name="Lname" type="text">
if ($Lname meets some condition)
{
<input name="Number" type="text>
if ($Number meets some condition)
{
}
}
}
else;
echo "Please enter a phone number";
else;
echo "Please enter a valid last name";
else;
echo "Please enter a valid first name";
?>
>
I know the code isn't exact, I am just theorizing here. Could such a
thing be done? Even remotely similar? I don't really plan on doing this
anytime soon, but I was just curious. I only started PHP programming a
few days ago so no need to point out how stupid this may sound.
>

Jerim,

Yes and no.

First of all, the PHP code will be executed before the page is ever sent
to the client. It's not interactive like javascript is.

So what you do is have the user complete the form and submit it. Your
code should then validate all fields. But you don't want to nest your
statements like that - for instance, what happens if they don't enter
either a first name or a phone number? They'll get a single message
which they correct - and they'll get a second message.

Rather, process each field individually, i.e.


$emsg = '';
if ($fname = '') // No first name
$emsg .= "Please enter a first name.<br>\n";
if ($lname = '') // No last name
$emsg .= "Please enter a last name.<br>\n";
if ($phone = '') // No phone number
$emsg .= "Please enter a phone number<br>\n";

....

if ($emsg != '')
echo $emsg;


--
=============== ===
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attgl obal.net
=============== ===

[Gordon Burditt]

Re: Form validation

>I am looking into form validation for my HTML form. I don't want to use

>javascript and was looking into using PHP. A crazy thought crossed my
>mind and I just wanted to get some input.

>What if I basically made the form one long if/then statement? I could

HTML does not have if/then statements.

PHP runs server-side. It doesn't run until the user fills out the
whole form. If you want to ask for each individual item one at
a time, that's OK, but pretty darned annoying, and a lot of users
are going to give up.

JavaScript is often Turned Off (tm).

>ask for the first piece of information, test it against some
>conditions, then if it is okay I allow the user to fill in the next
>piece of information. I could go do down the page validation each box
>as we go. I could use hidden on all the text boxes until the previous
>condition had been validated.

Why? To annoy users and make them go away?

Note that you *MUST* validate any security-related restrictions on
the server side *ANYWAY* because spambots and thieves will probably
have Javascript turned off and bypass validation to steal stuff or
send SPAM through your server.

>Some pseudocode:
>
><?php
><form action=POST method=register ed.php>
><input name"Fname" type="text">
>if ($Fname meets some condition)
{
<input name="Lname" type="text">
if ($Lname meets some condition)
{
<input name="Number" type="text>
if ($Number meets some condition)
{
}
}
>}
>else;
echo "Please enter a phone number";
>else;
echo "Please enter a valid last name";
>else;
echo "Please enter a valid first name";
>?>
>
>I know the code isn't exact, I am just theorizing here. Could such a
>thing be done? Even remotely similar? I don't really plan on doing this
>anytime soon, but I was just curious. I only started PHP programming a
>few days ago so no need to point out how stupid this may sound.
>

[Jerim79]

Re: Form validation


Jerry Stuckle wrote:

Jerim79 wrote:

I am looking into form validation for my HTML form. I don't want to use
javascript and was looking into using PHP. A crazy thought crossed my
mind and I just wanted to get some input.

What if I basically made the form one long if/then statement? I could
ask for the first piece of information, test it against some
conditions, then if it is okay I allow the user to fill in the next
piece of information. I could go do down the page validation each box
as we go. I could use hidden on all the text boxes until the previous
condition had been validated. Some pseudocode:

<?php
<form action=POST method=register ed.php>
<input name"Fname" type="text">
if ($Fname meets some condition)
{
<input name="Lname" type="text">
if ($Lname meets some condition)
{
<input name="Number" type="text>
if ($Number meets some condition)
{
}
}
}
else;
echo "Please enter a phone number";
else;
echo "Please enter a valid last name";
else;
echo "Please enter a valid first name";
?>

I know the code isn't exact, I am just theorizing here. Could such a
thing be done? Even remotely similar? I don't really plan on doing this
anytime soon, but I was just curious. I only started PHP programming a
few days ago so no need to point out how stupid this may sound.

>
Jerim,
>
Yes and no.
>
First of all, the PHP code will be executed before the page is ever sent
to the client. It's not interactive like javascript is.
>
So what you do is have the user complete the form and submit it. Your
code should then validate all fields. But you don't want to nest your
statements like that - for instance, what happens if they don't enter
either a first name or a phone number? They'll get a single message
which they correct - and they'll get a second message.
>
Rather, process each field individually, i.e.
>
>
$emsg = '';
if ($fname = '') // No first name
$emsg .= "Please enter a first name.<br>\n";
if ($lname = '') // No last name
$emsg .= "Please enter a last name.<br>\n";
if ($phone = '') // No phone number
$emsg .= "Please enter a phone number<br>\n";
>
...
>
if ($emsg != '')
echo $emsg;
>
>
--
=============== ===
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attgl obal.net
=============== ===

Thanks for the info, it was very useful and informative.

[Jerim79]

Re: Form validation


Jerim79 wrote:

I am looking into form validation for my HTML form. I don't want to use
javascript and was looking into using PHP. A crazy thought crossed my
mind and I just wanted to get some input.
>
What if I basically made the form one long if/then statement? I could
ask for the first piece of information, test it against some
conditions, then if it is okay I allow the user to fill in the next
piece of information. I could go do down the page validation each box
as we go. I could use hidden on all the text boxes until the previous
condition had been validated. Some pseudocode:
>
<?php
<form action=POST method=register ed.php>
<input name"Fname" type="text">
if ($Fname meets some condition)
{
<input name="Lname" type="text">
if ($Lname meets some condition)
{
<input name="Number" type="text>
if ($Number meets some condition)
{
}
}
}
else;
echo "Please enter a phone number";
else;
echo "Please enter a valid last name";
else;
echo "Please enter a valid first name";
?>
>
I know the code isn't exact, I am just theorizing here. Could such a
thing be done? Even remotely similar? I don't really plan on doing this
anytime soon, but I was just curious. I only started PHP programming a
few days ago so no need to point out how stupid this may sound.

I am just starting work on editing a PHP script that someone else in
the company wrote. I noticed that this person chose to use different
PHP pages depending on the error. For instance, the main form contains
input boxes for Name, Address, Telephone and Email. When submitted, the
form calls a file called verify_email.ph p. This file runs an if/then
statement. If the email is valid it calls another form, such as
verify_name and so on until everything is validated and the information
is written to the database. If the email is invalid, it displays a new
form which is similar to the original form, only this one has the email
box highlighted in red and asks the user to enter the email again. All
the input boxes are already filled in as the coder chose to use PHP
variables to re-enter the information for the customer, instead of
having to start over.

The question I have is, is this an "acceptable " way to handle error
messages. Being quite new to PHP I don't know what to make of this
method.

[Geoff Berrow]

Re: Form validation

Message-ID: <1163196797.736 817.324440@m7g2 000cwm.googlegr oups.comfrom
Jerim79 contained the following:

>The question I have is, is this an "acceptable " way to handle error
>messages. Being quite new to PHP I don't know what to make of this
>method.

That's very subjective. It may not be terribly elegant but it also may
be that this solution makes it clear to see what is going on.

In judging 'acceptability' factors to consider are:

Is the code secure, independent of user configuration?
Does the code use significantly more resources than it should?
Is the code easy to follow, maintain and update?
Is the solution good and clear from the user's point of view?



--
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/

[Jerim79]

Re: Form validation


Geoff Berrow wrote:

Message-ID: <1163196797.736 817.324440@m7g2 000cwm.googlegr oups.comfrom
Jerim79 contained the following:
>

The question I have is, is this an "acceptable " way to handle error
messages. Being quite new to PHP I don't know what to make of this
method.

>
>
That's very subjective. It may not be terribly elegant but it also may
be that this solution makes it clear to see what is going on.
>
In judging 'acceptability' factors to consider are:
>
Is the code secure, independent of user configuration?
Does the code use significantly more resources than it should?
Is the code easy to follow, maintain and update?
Is the solution good and clear from the user's point of view?
>
>
>
--
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/

How can you determine the resources that the code will use? Is there a
measurable way to determine which code is more "efficient" in terms of
resources?

You ask if the code is easy to follow, maintain and update? I would say
that yes, it is, since even a beginner like myself figured out what the
code was doing. However, certainly in any language there may be faster,
harder to understand shortcuts to any solution that a beginner may not
be aware of. Should we always strive to use a simpler method that
everyone can figure out, or should we look to use the most advanced
techniques that may be more efficient but alienate younger, less
experienced programmers?

[Geoff Berrow]

Re: Form validation

Message-ID: <1163430484.409 239.94080@h54g2 000cwb.googlegr oups.comfrom
Jerim79 contained the following:

>How can you determine the resources that the code will use? Is there a
>measurable way to determine which code is more "efficient" in terms of
>resources?

Well I'd say it would be some intensive process such as image
manipulation. If the script constantly generated, say, thumbnails on
the fly instead of generating them once then subsequently using the
pre-generated image, then that would obviously use considerably more
resources. Speed differences are often discussed here, but often the
differences are small fractions of a second.

>
>You ask if the code is easy to follow, maintain and update? I would say
>that yes, it is, since even a beginner like myself figured out what the
>code was doing. However, certainly in any language there may be faster,
>harder to understand shortcuts to any solution that a beginner may not
>be aware of. Should we always strive to use a simpler method that
>everyone can figure out, or should we look to use the most advanced
>techniques that may be more efficient but alienate younger, less
>experienced programmers?

I'd say it was personal preference. I happen to think a bit of extra
verbosity is no bad thing if it improves clarity but obviously, mileage
varies.
--
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/