How can I check if a char is a letter or a number?

Question

I have a string and I want to loop it so that I can check if every char is a letter or number.

$s = "rfewr545 345b";

for ($i=1; $i<=strlen($s); $i++){
   if ($a[$i-1] == is a letter){
      echo $a[$i-1]." is a letter";
   } else {
      echo $a[$i-1]." is a number";
   }
}

How can I check if a char is a letter or a number?

Answer 1

You can use:

ctype_digit

and

ctype_alpha