[SOLVED] Validating a field - no invalid chars or spaces

[JSHINER]

I have this to check for invalid chars:

 

<?php

  if (!preg_match('/^[a-zA-Z]$/',$data) {
    echo "FAIL - invalid username";
  }

?>

 

But how do I also get it to check for spaces.

[rhodesa]

are you saying you want to allow spaces in your usernames? currently, this check will only allow lower case and upper case letters. to allow spaces too it would be:

 

<?php

  if (!preg_match('/^[a-zA-Z ]$/',$data) {
    echo "FAIL - invalid username";
  }

?>

[JSHINER]

I only want to allow upper/lowercase letters and numbers - no special characters or spaces allowed.

[samshel]

this will give small case, upper case letters and numbers only

 

<?php

  if (!preg_match('/^[a-zA-Z0-9]+$/',$data) {
    echo "FAIL - invalid username";
  }

?>

 

PS: added a + at the end to allow more than one charachters. i think you need that ?

[rhodesa]

this will give small case, upper case letters and numbers only

 

<?php

  if (!preg_match('/^[a-zA-Z0-9]+$/',$data) {
    echo "FAIL - invalid username";
  }

?>

 

PS: added a + at the end to allow more than one charachters. i think you need that ?

 

what they said....and you'll definitely need the plus...

[JSHINER]

Works great. Thanks!

 

Yes, generally more than one character helps in usernames