Function to check characters not working correctly?

Petraverse

Hi,

I created this function

<?php
function username_bad_chars($input) {
	$legal_chars_sql = "SELECT * FROM un_legal_chars";
	$legal_chars_res = mysql_query($legal_chars_sql);
	while($legal_chars_row = mysql_fetch_array($legal_chars_res)) {
		$input_new = str_replace($legal_chars_row['char'], "", $input);
	}
	if($input_new != "") {
		return 1;
	} else {
		return 0;
	}
}
?>

The table 'un_legal_chars' contains just one column called 'char' and is populated with letters a thru z and numbers 0 through 9 and _ and one row which is just a space (so that the $input can have a space in it like 'the input'). The idea is that if the $input contains any other characters the function will return 1 (true)... But it ALWAYS returns 1 (true) even if the characters are all in the database. Any suggestions?

Thanks

planetsim

You should probably use a regular expression to do this. A lot faster.

And your $input_new is always going to return true as its being executed throughout the loop, even if there is nothing to replace.

Petraverse

Hi,

I'm no good with regular expressions 😛 Any help with that would be appreciated...

Also, I'm not sure I understand correctly. After I replace all LEGAL characters with nothing, the string should be nothing, right? So then if($input_new != "") then that should mean that there is an illegal character, no?

Thanks
Max

planetsim

No your $input_new should get the value of $input. Why not echo out your $input_new

Also what are the valid characters?

planetsim

if (preg_match("/[^a-zA-Z0-9_ ]/ims",$string)) {
  echo 'invalid';
} else {
  echo 'valid';
}

Whipped that up with just a-z and A-Z and numbers allowed. Not sure if thats all the allowed characters though.

Petraverse

Hi,

Thag's great, but could you tell me how to make it also allow underscores (_) and spaces ( )?

Thanks
Max

Petraverse

Hi,

That doesn't seem to work... On the if() statement i says parse error unexpected '{' on line 149 (the if(preg_match()) { line).

Any ideas?

Thanks
Max

tsinka

Hi,

use that code to allow underscores and spaces:

if (preg_match("/[^a-zA-Z0-9]/ims",$string)) { 
  echo 'invalid'; 
} else { 
  echo 'valid'; 
}

About that syntax error. Make sure that there are two closing brackets after $string (just guessing).

Post the code if that doesn't work
Thomas

Petraverse

Hi,

I have this...

function username_bad_chars($input) {
	$input = strtolower($input);
	if(preg_match("/[^a-z0-9_ ]/ims",$input))_{
		return 0;
	}_else_{
		return 1;
	}
}

And am getting the parse error on line 149 (the line with the if() statement)

Petraverse

In my code I don't have }else{ I have } else { I don't know why it did that...

tsinka

Hi,

please post the code attached to your post (renamed to .txt) if the code isn't confidential 🙂

Maybe some "invisible" special chars ?

Thomas

Petraverse

Hi,

Quite a lot of the code is confidential yes, but the only difference between the posted code and my code is the }else{ - checked myself 😃

tsinka

Ok,

so ... dou you still have that error or is it solved ?

Thomas

Petraverse

Yes, I still have that error.

tsinka

Ok,

let's try again, replace the code in your script by copy'n'pasting the follwoing code over the existing:

function username_bad_chars($input) { 
    $input = strtolower($input); 
    if (preg_match("/[^a-z0-9]/ims",$input)) { 
        return 0; 
    } else { 
        return 1; 
    } 
}

I removed the _ and space (you wrote that you'd like to allow underscores and spaces somewhere earlier).

Thomas

Petraverse

Hi,

Found the problem. I copy and pasted that code and got errors. I just re-wrote each line character for character and no errors now 🙂

Just got to see if it works now 😃

Thanks
Max

Petraverse

Hi...back with the same problem I posted with...in reverse... It's returning false every time now 😛

Any ideas?

function username_bad_chars($input) {
	$input = strtolower($input);
	if(preg_match("/[^a-z0-9]/ims", $input)) {
		return_0;
	} else {
		return_1;
	}
}

tsinka

Hi,

I made a mistake in my post with code. Add the underscore and the space to the pattern again in order to allow them.

About the problem:

Please retype the two return lines. There are underscores in it. With theses underscores you always get false. And I'd suggest to rather use true and false instead of 1 and 0.

btw...which editor do you use.

Thomas

Petraverse

Hi,

There isn't actually underscores in the return lines, vBulletin is just funky with posting PHP 😃

Any ideas?

Petraverse

Hi,

I got it... for anyone who is wondering here it goes

function username_bad_chars($input) {
	return eregi("[^a-zA-Z0-9_ ]", $input);
}

Thanks all