Php implements common credit card verification and php universal credit card verification

Php implements common credit card verification and php universal credit card verification

This example describes how php implements a common credit card verification class. Share it with you for your reference.

The original text is described as follows:

Credit Card Validation Solution (PHP Edition)
Version 3.5:

Description
Credit Card Validation Solution™Uses a four step process to ensure credit card numbers are keyed in correctly. this procedure accurately checks cards from American Express, financialian BankCard, Carte Blache, Diners Club, Discover/Novus, JCB, MasterCard and Visa.
For more information, please read the comments in the code itself.

Installation Instructions
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The Code is as follows:

<?php# ------------------------------------------------------------------------# Credit Card Validation Solution, version 3.5         PHP Edition# 25 May 2000## COPYRIGHT NOTICE:# a) This code is property of The Analysis and Solutions Company.# b) It is being distributed free of charge and on an "as is" basis.# c) Use of this code, or any part thereof, is contingent upon leaving#   this copyright notice, name and address information in tact.# d) Written permission must be obtained from us before this code, or any#   part thereof, is sold or used in a product which is sold.# e) By using this code, you accept full responsibility for its use#   and will not hold the Analysis and Solutions Company, its employees#   or officers liable for damages of any sort.# f) This code is not to be used for illegal purposes.# g) Please email us any revisions made to this code.## Copyright 2000         http://www.AnalysisAndSolutions.com/code/# The Analysis and Solutions Company     info@AnalysisAndSolutions.com# ------------------------------------------------------------------------## DESCRIPTION:# Credit Card Validation Solution uses a four step process to ensure# credit card numbers are keyed in correctly. This procedure accurately# checks cards from American Express, Australian BankCard, Carte Blache,# Diners Club, Discover/Novus, JCB, MasterCard and Visa.## CAUTION:# CCVS uses exact number ranges as part of the validation process. These# ranges are current as of 20 October 1999. If presently undefined ranges# come into use in the future, this program will improperly deject card# numbers in such ranges, rendering an error message entitled "Potential# Card Type Discrepancy." If this happens while entering a card & type# you KNOW are valid, please contact us so we can update the ranges.## POTENTIAL CUSTOMIZATIONS:# * If you don't accept some of these card types, edit Step 2, using pound# signs "#" to comment out the "elseif," "$CardName" and "$ShouldLength"# lines in question.# * Additional card types can be added by inserting new "elseif,"# "$CardName" and "$ShouldLength" lines in Step 2.# * The three functions here can be called by other PHP documents to check# any number.## CREDITS:# We learned of the Mod 10 Algorithm in some Perl code, entitled# "The Validator," available on Matt's Script Archive,# http://worldwidemart.com/scripts/readme/ccver.shtml. That code was# written by David Paris, who based it on material Melvyn Myers reposted# from an unknown author. Paris credits Aries Solis for tracking down the# data underlying the algorithm. At the same time, our code bears no# resemblance to its predecessors. CCValidationSolution was first written# for Visual Basic, on which Allen Browne and Rico Zschau assisted.# Neil Fraser helped prune down the OnlyNumericSolution() for Perl.function CCValidationSolution ($Number) {  global $CardName;  # 1) Get rid of spaces and non-numeric characters.  $Number = OnlyNumericSolution($Number);  # 2) Do the first four digits fit within proper ranges?  #   If so, who's the card issuer and how long should the number be?  $NumberLeft = substr($Number, 0, 4);  $NumberLength = strlen($Number);  if ($NumberLeft >= 3000 and $NumberLeft <= 3059) {    $CardName = "Diners Club";    $ShouldLength = 14;  } elseif ($NumberLeft >= 3600 and $NumberLeft <= 3699) {    $CardName = "Diners Club";    $ShouldLength = 14;  } elseif ($NumberLeft >= 3800 and $NumberLeft <= 3889) {    $CardName = "Diners Club";    $ShouldLength = 14;  } elseif ($NumberLeft >= 3400 and $NumberLeft <= 3499) {    $CardName = "American Express";    $ShouldLength = 15;  } elseif ($NumberLeft >= 3700 and $NumberLeft <= 3799) {    $CardName = "American Express";    $ShouldLength = 15;  } elseif ($NumberLeft >= 3528 and $NumberLeft <= 3589) {    $CardName = "JCB";    $ShouldLength = 16;  } elseif ($NumberLeft >= 3890 and $NumberLeft <= 3899) {    $CardName = "Carte Blache";    $ShouldLength = 14;  } elseif ($NumberLeft >= 4000 and $NumberLeft <= 4999) {    $CardName = "Visa";    if ($NumberLength > 14) {      $ShouldLength = 16;    } elseif ($NumberLength < 14) {      $ShouldLength = 13;    } else {      echo "<br /><em>The Visa number entered, $Number, in is 14 digits long.<br />Visa cards usually have 16 digits, though some have 13.<br />Please check the number and try again.</em><br />n";      return FALSE;    }  } elseif ($NumberLeft >= 5100 and $NumberLeft <= 5599) {    $CardName = "MasterCard";    $ShouldLength = 16;  } elseif ($NumberLeft == 5610) {    $CardName = "Australian BankCard";    $ShouldLength = 16;  } elseif ($NumberLeft == 6011) {    $CardName = "Discover/Novus";    $ShouldLength = 16;  } else {    echo "<br /><em>The first four digits of the number entered are $NumberLeft. <br />If that's correct, we don't accept that type of credit card.<br />If it's wrong, please try again.</em><br />n";    return FALSE;  }  # 3) Is the number the right length?  if ($NumberLength <> $ShouldLength) {    $Missing = $NumberLength - $ShouldLength;    if ($Missing < 0) {      echo "<br /><em>The $CardName number entered, $Number, is missing " . abs($Missing) . " digit(s).<br />Please check the number and try again.</em><br />n";    } else {      echo "<br /><em>The $CardName number entered, $Number, has $Missing too many digit(s).<br />Please check the number and try again.</em><br />n";    }    return FALSE;  }  # 4) Does the number pass the Mod 10 Algorithm Checksum?  if (Mod10Solution($Number) == TRUE) {    return TRUE;  } else {    echo "<br /><em>The $CardName number entered, $Number, is invalid.<br />Please check the number and try again.</em><br />n";  return FALSE;  }}function OnlyNumericSolution ($Number) {  # Remove any non numeric characters.  # Ensure number is no more than 19 characters long.  return substr( ereg_replace( "[^0-9]", "", $Number) , 0, 19);}function Mod10Solution ($Number) {  $NumberLength = strlen($Number);  $Checksum = 0;  # Add even digits in even length strings  # or odd digits in odd length strings.  for ($Location = 1 - ($NumberLength % 2); $Location < $NumberLength; $Location += 2) {    $Checksum += substr($Number, $Location, 1);  }  # Analyze odd digits in even length strings  # or even digits in odd length strings.  for ($Location = ($NumberLength % 2); $Location < $NumberLength; $Location += 2) {    $Digit = substr($Number, $Location, 1) * 2;    if ($Digit < 10) {      $Checksum += $Digit;    } else {      $Checksum += $Digit - 9;    }  }  # Is the checksum divisible by ten?  return ($Checksum % 10 == 0);}# ----------- BEGIN SAMPLE USER INTERFACE SECTION ------------## This section provides a simple sample user interface for the# Credit Card Validation functions. It generates an HTML form# where you enter a card number to check.#  # If a number has been posted by the form, check it.  if ( isset($Number) ) {    # Get rid of spaces and non-numeric characters in posted    # numbers so they display correctly on the input form.    $Number = OnlyNumericSolution($Number);    if (CCValidationSolution($Number) == TRUE) {      echo "<br />The $CardName number entered, $Number, <em>is</em> valid.<br />n";    }  } else {    $Number = "";  }  # Setup an input form. Posting it calls this page again.  echo "<form method="post" action="$REQUEST_URI">n";  echo "<br />Credit Card Number: <input type="text" name="Number" value="$Number">n";  echo "<input type="Submit" name="submitr" value="Check its Validity">n";  echo "</form><br />n";## ------------ END SAMPLE USER INTERFACE SECTION -------------?>

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