Detecting illegal chars with preg_match

[Sen7inel]

Hi,

I'm using

preg_match("/[^a-zA-Z0-9.@_\-]/", $str)

to detect illegal or possibly "dangerous" characters from input. It works all right, but just out of curiosity, why doesn't this just evaluate the first character of $str?

 

[shagymoe]

I didn't test it, but I'm pretty sure you have to place the ^ before the character class, like this:

preg_match("/^[a-zA-Z0-9.@_\-]/", $str)

 

[youradds]

preg_match("/^[a-zA-Z0-9.@_\-]$/", $str);

or a shorted version;

preg_match("/^[\w\d.@_\-]$/", $str);

Cheers

Andy