Translator

[JenL]

Hee guys,

 

We are building a PHP translater to generate the caesar code. Like A = B B = C etc. We want that other people who visite our website, can choose which rotation they would have. so rot 1 = A + 1, Rot 2 = A + 2 ( A=C), we built the follow code:

 

<?php

function translate($string)

{

        $code = array ('a','b','c','d','e','f');

        $translate = array ('b','c','d','e','f','g');

return str_replace($code,$translate,$string);

}

Echo translate('abcdef');

?>

 

How could you built a code if other people want an other rotation? so they can choose for more then one rotation.

 

Thank you

 

Greats Jeanine en Lotte

 

[Muddy_Funster]

use chr() = chr+$noOfTurns in place of the hard set translate array.  you will need to itterate it through the lenth of the $string input using substr.

[ignace]

Here's a little class I wrote that will do what you want:

 

class CaesarCode {
    private static $alfabetUpper;
    private static $alfabetLower;
    
    private $steps;
    
    private function _getNewPosition($originalPosition) {
        return ($originalPosition + $this->steps) % 26;
    }
    
    private function _getCharFromArray($char, $fromArray) {
        if (($charKey = array_search($char, $fromArray)) !== false) {
            return $fromArray[$this->_getNewPosition($charKey)];
        }
        return false;
    }
    
    private function _translateChar($char) {
        $translatedChar = $this->_getCharFromArray($char, $this->_getAlfabetUpper());
        if ($translatedChar === false) {
            $translatedChar = $this->_getCharFromArray($char, $this->_getAlfabetLower());
        }
        return $translatedChar;
    }
    
    private function _getAlfabetUpper() {
        if (empty(self::$alfabetUpper)) {
            self::$alfabetUpper = range('A', 'Z');
        }
        return self::$alfabetUpper;
    }
    
    private function _getAlfabetLower() {
        if (empty(self::$alfabetLower)) {
            self::$alfabetLower = range('a', 'z');
        }
        return self::$alfabetLower;
    }
    
    public function __construct($steps) {
        $this->steps = $steps;
    }
    
    public function translate($string) {
        $encr = '';
        foreach (str_split($string) as $key => $char) {
            if (($newChar = $this->_translateChar($char)) !== false)
                $char = $newChar;
            $encr .= $char;
        }
        return $encr;
    }
}

 

Use it like:

 

$code = new CaesarCode(13);
echo $code->translate('Hello World!');

[JenL]

O cool Really thanks!