Hmmm I hate PREG

jstraa

I want to test a string only that only can contain A-Z a-z 0-9 and dots (.) What is the PREG function for this?

Thanks in advance !

Jeroen

swr

if (preg_match('/^{[A-Za-z0-9.]*$/',} $your_string)) {
echo "String contains only alphanumeric or dot.".
}

jstraa

Unbelievable you can do this so fast, I wish I had the knowledge to build a preg composer to make life easy 😉

Thanks !

pyro

Might I be picky and state that the should be a +, as the will allow an empty string to validate? Furthermore, you do not have to escape the . in the character class. Lastly, you have a . rather than a ; at the end of the echo line... 😉

You could also shorten it a bit by using the i flag, to denote case insensativity.

if (preg_match('/^[a-z0-9.]+$/i', $foo)) {
	echo "string validates";
}

Moonglobe

or just use \w....

if (preg_match('/^[\\w.]+$/', $foo)) {
    echo "string validates";
}

note that the dot's still there.

pyro

Yes, as long as your realize that \w also includes the _. 😉

Moonglobe

well yah, obviously.... but if you're using the underscore for something special, i dont quite get your logic..... so it should be allowed.

pyro

Just thought I should mention it, as jstraa did not include it in the list of valid characters.

jstraa

Thanks to you all, the _ was not mentioned indeed ...
I needed this to perform a check to make sure people cannot hack into my system, the line get's tested first to prevent that people can enter system commando's (with the exec) command, in this way people cannot enter spaces etc so I guess I'm safe now !

Regards,

Jeroen