PHP: How to tell if a string contains any special characters?

Question

I am using pspell to spell check some words. However if the word is something like G3523B it clearly is not a misspelled word but pspell changes it to GB. I would like somehow to qualify a word as a word before trying to spell check it. Maybe checking to see if the string contains any numbers or special characters.

So what is the best way to check a string for special chars or digits?

(if someone has a better idea to achieve what I am after please share)

Answer 1

How about using a regex:

if (preg_match('/[^z-zA-Z]+/', $your_string, $matches))
{
  echo 'Oops some number or symbol encountered !!';
}
else
{
  // everything fine...
}

Answer 2

If you just want to check whether the string $input consists only of characters a-z and A-Z you can use the following:

if(!preg_match('/^\[a-zA-Z]+$/',$input)) {
   // String contains not allowed characters ...
}