PHP form validation

[jo.nova]

[b]I'm trying to figure out how to validate form fields using PHP.  My form already checks for empty fields, but I would also like to validate the email format and the minimum phone number length. 

Any suggestions? Or links to some good scripts for this purpose?
[/b]

[designationlocutus]

Have a look into the [b]ereg()[/b] function over at php.net. If you're doing form validation, it might be worth you looking into regular expressions.

[Daniel0]

In my opinion [url=http://php.net/preg_match]preg_match[/url] is better.

[Ninjakreborn]

[code]$regex = "^[A-Za-z0-9\._-]+@([A-Za-z0-9][A-Za-z0-9-]{1,62})(\.[A-Za-z][A-Za-z0-9-]{1,62})+$";[/code]
Make that a variable that can be accessed by the script
then pass this into the script
[code]if (!ereg("$regex", $_POST['email'])) { //tests emails format with regex variable above
$errorhandler .= "The email address is improperly formatted<br />";
}[/code]
The $_POST['email']
will be the name of your variable.
The errorhandler is what I use to record the errors but handle them however you want the important part is
if (!ereg( and the rest of it until )) {
That is the most important if the email is not formatted like
something@something.com
then it returns false/

[designationlocutus]

[quote author=Daniel0 link=topic=100058.msg394452#msg394452 date=1152542894]
In my opinion [url=http://php.net/preg_match]preg_match[/url] is better.
[/quote]
Hmm what are a major advantages over each?

[Daniel0]

[quote author=designationlocutus link=topic=100058.msg394458#msg394458 date=1152543082]
[quote author=Daniel0 link=topic=100058.msg394452#msg394452 date=1152542894]
In my opinion [url=http://php.net/preg_match]preg_match[/url] is better.
[/quote]
Hmm what are a major advantages over each?
[/quote]

I find preg_match faster and ereg is not binary-safe.

[designationlocutus]

[quote author=Daniel0 link=topic=100058.msg394463#msg394463 date=1152543403]
[quote author=designationlocutus link=topic=100058.msg394458#msg394458 date=1152543082]
[quote author=Daniel0 link=topic=100058.msg394452#msg394452 date=1152542894]
In my opinion [url=http://php.net/preg_match]preg_match[/url] is better.
[/quote]
Hmm what are a major advantages over each?
[/quote]

I find preg_match faster and ereg is not binary-safe.
[/quote]

Hmm might have to give both functions a whizz and give them some difficult data to play with :) Thanks for the answer.

[Ninjakreborn]

Preg match or ereg can be used interchangeably, it just has different syntax rules, one is based on Perl regular expressions hte other is based on post ix(?) I think it is
One is better than the other, pregmatch statistically is better and has more performance.
But ereg is good for small things, like checking emails, or whatever, and I think pregmatch has slightly harder to understand syntax, but it's better overall, atleast by what I have studied

[designationlocutus]

Hmm so for the process of validating small form data use ereg() and preg_match() for larger dataset. You know it might be a good convention to use ereg() with varchar fields and preg_match () for the larger blobs and text fields.

[brown2005]

i use

if (!eregi ("^([a-z0-9_]|\\-|\\.)+@(([a-z0-9_]|\\-)+\\.)+[a-z]{2,4}$", $emailfield))

to check my email field.... works well...