php version a javascript function...(postcode validation)

Question

I am looking for a way to achieve this in PHP...

var newPostCode = checkPostCode  (document.getElementById('Postcode').value);
  if (newPostCode) {
    document.getElementById('Postcode').value = newPostCode;
    return true;
  } 
  else alert ("Postcode has invalid format");
    return false;
}

The code in question is used on a html form, to valid postcodes, as per this websites instructions http://www.braemoor.co.uk/software/postcodes.shtml but there are no instructions on how to call the php function that i need only a demonstration of the javascript method.

The current code is javascript, and i have only recently discovered that my javascript function can be bypassed quite easily. So i am now looking to php to achieve the same, but serverside.

The main thing this code does is `document.getElementById`, which is simply not applicable to PHP at all. What exactly is your problem in creating a PHP version of "this code"? — deceze, Nov 28 '13 at 15:07
Javascript validation is only a matter of UX. Server-side validation is the only true validation. Unfortunately, there's no validation rule for us to see in the code here above... — Laurent S., Nov 28 '13 at 15:08
I am not at a confident enough skill level to write my own scripts hence why i use other people scripts and the website i got the script from only supplied me with the information for the javascript version, but i later realised i need serverside validation, to which a script has been written but i was unable to implement it im hoping Barmar's solution is what im looking for as it makes more sense to me now. — andy_baz, Nov 28 '13 at 15:16

score 1 · Answer 1 · answered Nov 28 '13 at 15:07

1

$newPostCode = checkPostCode($_POST['Postcode']);
if ($newPostCode) {
    // Do stuff with $newPostCode
} else {
    echo "Postcode has invalid format";
}

You'll still need to write the checkPostCode() function.

answered Nov 28 '13 at 15:07

Barmar

741,623
53
500
612

thanks for this speedy response, i have already acquired the checkpostcode function from the website listed in the original post. My php ability is only at the level of being able to read, writing scripts still intimidates me! – andy_baz Nov 28 '13 at 15:09

score 0 · Answer 2 · answered Nov 28 '13 at 15:07

<?php
/*==============================================================================
Application:   Utility Function
Author:        John Gardner

Version:       V1.0
Date:          25th December 2004
Description:   Used to check the validity of a UK postcode

Version:       V2.0
Date:          8th March 2005
Description:   BFPO postcodes implemented.
               The rules concerning which alphabetic characters are alllowed in 
               which part of the postcode were more stringently implementd.

Version:       V3.0
Date:          8th August 2005
Description:   Support for Overseas Territories added            

Version:       V3.1
Date:          23rd March 2008
Description:   Problem corrected whereby valid postcode not returned, and 
                             'BD23 DX' was invalidly treated as 'BD2 3DX' (thanks Peter 
               Graves)              

Version:       V4.0
Date:          7th October 2009
Description:   Character 3 extended to allow 'pmnrvxy' (thanks to Jaco de Groot)           

Version:       V4.1
Date:          8th Septemeber 2011
Description:   ereg and ereg_replace replaced with preg_match and preg_replace
               BFPO support improved
               Add check for Anquilla

Version:       V5.0
Date:          8th November 2012
               Specific support added for new BFPO postcodes 

Parameters:    $postcode - postcode to be checked. This is returned reformatted 
               if valid.

This function checks the value of the parameter for a valid postcode format. The 
space between the inward part and the outward part is optional, although is 
inserted if not there as it is part of the official postcode.

The functions returns a value of false if the postcode is in an invalid format, 
and a value of true if it is in a valid format. If the postcode is valid, the 
parameter is loaded up with the postcode in capitals, and a space between the 
outward and the inward code to conform to the correct format.

Example call:

    if (!checkPostcode ($postcode) ) {
      echo 'Invalid postcode <br>';
    }

------------------------------------------------------------------------------*/
function checkPostcode (&$toCheck) {

  // Permitted letters depend upon their position in the postcode.
  $alpha1 = "[abcdefghijklmnoprstuwyz]";                          // Character 1
  $alpha2 = "[abcdefghklmnopqrstuvwxy]";                          // Character 2
  $alpha3 = "[abcdefghjkpmnrstuvwxy]";                            // Character 3
  $alpha4 = "[abehmnprvwxy]";                                     // Character 4
  $alpha5 = "[abdefghjlnpqrstuwxyz]";                             // Character 5
  $BFPOa5 = "[abdefghjlnpqrst]{1}";                               // BFPO character 5
  $BFPOa6 = "[abdefghjlnpqrstuwzyz]{1}";                          // BFPO character 6

  // Expression for BF1 type postcodes 
  $pcexp[0] =  '/^(bf1)([[:space:]]{0,})([0-9]{1}' . $BFPOa5 . $BFPOa6 .')$/';

  // Expression for postcodes: AN NAA, ANN NAA, AAN NAA, and AANN NAA with a space
  $pcexp[1] = '/^('.$alpha1.'{1}'.$alpha2.'{0,1}[0-9]{1,2})([[:space:]]{0,})([0-9]{1}'.$alpha5.'{2})$/';

  // Expression for postcodes: ANA NAA
  $pcexp[2] =  '/^('.$alpha1.'{1}[0-9]{1}'.$alpha3.'{1})([[:space:]]{0,})([0-9]{1}'.$alpha5.'{2})$/';

  // Expression for postcodes: AANA NAA
  $pcexp[3] =  '/^('.$alpha1.'{1}'.$alpha2.'{1}[0-9]{1}'.$alpha4.')([[:space:]]{0,})([0-9]{1}'.$alpha5.'{2})$/';

  // Exception for the special postcode GIR 0AA
  $pcexp[4] =  '/^(gir)([[:space:]]{0,})(0aa)$/';

  // Standard BFPO numbers
  $pcexp[5] = '/^(bfpo)([[:space:]]{0,})([0-9]{1,4})$/';

  // c/o BFPO numbers
  $pcexp[6] = '/^(bfpo)([[:space:]]{0,})(c\/o([[:space:]]{0,})[0-9]{1,3})$/';

  // Overseas Territories
  $pcexp[7] = '/^([a-z]{4})([[:space:]]{0,})(1zz)$/';

  // Anquilla
  $pcexp[8] = '/^ai-2640$/';

  // Load up the string to check, converting into lowercase
  $postcode = strtolower($toCheck);

  // Assume we are not going to find a valid postcode
  $valid = false;

  // Check the string against the six types of postcodes
  foreach ($pcexp as $regexp) {

    if (preg_match($regexp,$postcode, $matches)) {

      // Load new postcode back into the form element  
          $postcode = strtoupper ($matches[1] . ' ' . $matches [3]);

      // Take account of the special BFPO c/o format
      $postcode = preg_replace ('/C\/O([[:space:]]{0,})/', 'c/o ', $postcode);

      // Take acount of special Anquilla postcode format (a pain, but that's the way it is)
      if (preg_match($pcexp[7],strtolower($toCheck), $matches)) $postcode = 'AI-2640';      

      // Remember that we have found that the code is valid and break from loop
      $valid = true;
      break;
    }
  }

  // Return with the reformatted valid postcode in uppercase if the postcode was 
  // valid
  if ($valid){
      $toCheck = $postcode; 
        return true;
    } 
    else return false;
}
?>

php version a javascript function...(postcode validation)

2 Answers2