Regula Expression Help

earthlingzed

I am trying to validate username and password input when new users sign up at my site and need help putting together a regular expression to validate their input.

The criteria is as follows:

alpha numeric username and pass
3 to 15 characters in length
no capital letters
no spaces

What I have so far is something like this:
[a-z0-9]{3,15}
But this does not have any space checking, and I am unsure if it is written correctly.

stolzyboy

to have no capital letters, run the variable thru [man]strotolower[/man], to check the length of the string, run it thru [man]strlen[/man], and to check for a space use [man]strpos[/man]

earthlingzed

I took your advice on the strpos trick and put togther the following. It is still not validating (passes test even when usernaem has spaces). Can anyone see where I am going wrong?

$uname_test = strpos(" ", $username);
$pass_test = strpos(" ", $pass);
if($uname_test != false || $pass_test != false){
echo "Username Test: ".$uname_test."<br>Pass Test: ".$pass_test;
#send message
$_SESSION["message"] = "User name and password can not contain spaces.";
#redirect
session_unregister("page_type");
header("Location:mk_profile.php");
exit;
}

stolzyboy

you need to so something like

if (strpos(" ", $pass))
{
//there is a space
}
else
{
//there isn't
}

earthlingzed

I found a good solution to my problem. Using strpos() was not working for me but I did discover the correct wayt o detect spaces with a regular expression.

For future reference for anyone who may need it, the below expressions will look for spaces, lower case alphanumeric submissions without special chars:

if(ereg('[[:space:]]',$username) || ereg('[[:space:]]',$pass)){
		#send message
		$_SESSION["message"] = "User name and password can not contain spaces.";
		#redirect
	header("Location:mk_profile.php");
		exit;
	} 

if(!ereg('^[a-z0-9]{3,15}$',$username)){
	#send message
	$_SESSION["message"] = "User name must only contain lower case letters and/or numbers, no spaces, and should be 3 to 15 characters in length.";
	#redirect
header("Location:mk_profile.php");
		exit;
	}