[SOLVED] How can I check user input?

[bobleny]

How can I check $_POST['monkeys'] for the number of characters and what characters it contains?

 

I want to run scripts against their inputs...

[hitman6003]

strlen and strpos

 

http://www.php.net/strlen

http://www.php.net/strpos

[effigy]

Regular expressions are handy for performing advanced checks, if needed. See the links in my signature.

[bobleny]

What are regular expressions?

[effigy]

What are regular expressions?

 

See the links in my signature.

 

One of those links: Tutorial

 

P.S. We have a Regex Board.

[roopurt18]

Your first encounter with regular expressions is like falling into the lion exhibit at the zoo 15 minutes before the lions' regular feeding time.

 

Once you get familiar with them, your relationship with regexps is a lot like Siegfried and Roy's relationship with their tigers.  Usually you can get them to do what you want, you can even bully them a little, but it's only a matter of time before one eats you.

 

That said, regexps are a powerful string pattern-matching tool.  Honestly, you can't live without them.

[bobleny]

strlen and strpos should work fine for what I am doing.

 

Once I find a character, how do I replace it?

[effigy]

str_replace.

 

Please see the String Functions in the manual.

[bobleny]

Alright, thank you, this should work!

[bobleny]

Wait, let me ask another question on this....

 

$monkeys, may only contain letters and or numbers with no spaces.

 

$pass = strpos($monkeys, $legal);

if($pass === FALSE)

{

everything is good

}

else

{

$monkeys isn't alphanumeric

}

 

What should $legal be?

 

I got no idea how to do this...

 

Thanks!

[effigy]

The simplest way to check this is with regular expressions:

 

if (preg_match('/^[A-Za-z0-9]+\z/', $monkeys)) {
  // is valid
}
else {
  // is not valid
}

[bobleny]

Regular expressions, huh? That figures...

 

I guess I'll have to read up on that....

 

Alright then. Thanks a lot!