Validation function for numeric field

Question

I am finishing up this website and working on the last couple validations. How can I make the validation for a name field only accept letters and not numbers. And how can i validate a zip code field to contain exactly 5 digits. Below is what I have so far.

//First Name
function check_fname($fname){
if($fname==''){
    return 'Please Enter your First Name.';
}}

//Zip Code
function check_zip($zip){
if(! is_numeric($zip)){
    return 'Please Enter your Zip.';
}}

Validate functions should ONLY return BOOLEAN values. You are on the wrong track. This should be similar to this if ( ! is_zip_valid($zip) ){ /* add error message to container */ } — Yang
– Yang, Commented Apr 19, 2013 at 3:10

elclanrs · Accepted Answer · 2013-04-19 02:11:53Z

1

Regular expressions:

if (preg_match('/^[a-z]+$/i', $fname)) ... // At least one letter

if (preg_match('/^\d{5}$/', $zip)) ... // 5 digits

For the name, depending on your demographic you might want to allow foreign characters I recommend this solution which is more forgiving:

if (strlen($fname) > 0 && ! preg_match('/\d/', $fname)) ...

edited Apr 19, 2013 at 2:11

answered Apr 19, 2013 at 2:04

elclanrs

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1 Comment

Yang Over a year ago

if you talk about foreign chars, then mb_strlen($string, 'UTF-8') would make more sense.

VolCh · Accepted Answer · 2013-04-19 02:48:49Z

0

For any Unicode (international) letters

if (preg_match('/^\pL+$/u', $fname)) ...

answered Apr 19, 2013 at 2:48

VolCh

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