目標(biāo): 實(shí)現(xiàn)字符串移位加密.

缺點(diǎn): 密鑰傳輸

const DIC =':abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';

public static function sDecode($s)

{

$sKey? ? ? ='vjJ3LKNENnrvvRc9HPl5NxRQR5tRrHW';

$a? ? ? ? ? = str_split($s);

$aKey? ? ? = str_split($sKey);

$iKeyLength = count($aKey);

$aDic? ? ? = str_split(self::DIC);

$iDicLength = count($aDic);

$kp? ? ? ? =0;

$o? ? ? ? ? ='';

foreach ($a as $c) {

$step = ord($aKey[$kp %$iKeyLength]);

$dp? =self::ctn($c) -$step;

while ($dp <0) {

$dp +=$iDicLength;

}

//? ? ? ? ? ? echo $dp . chr(9) . $aDic[$dp] . chr(10);

? ? ? ? ? ? $o? ? .=$aDic[$dp];

$line = [$c,self::ctn($c),$step,$dp,$aDic[$dp]];

//? ? ? ? ? ? echo implode(chr(9), $line) . chr(10);

? ? ? ? ? ? $kp++;

}

return $o;

}

public static function sEncode($s)

{

$sKey? ? ? ='vjJ3LKNENnrvvRc9HPl5NxRQR5tRrHW';

$a? ? ? ? ? = str_split($s);

$aKey? ? ? = str_split($sKey);

$iKeyLength = count($aKey);

$aDic? ? ? = str_split(self::DIC);

$iDicLength = count($aDic);

$kp? ? ? ? =0;

$o? ? ? ? ? ='';

foreach ($a as $c) {

$n? ? =self::ctn($c);

$step = ord($aKey[$kp %$iKeyLength]);

//? ? ? ? ? ? echo $n.chr(9).$step.chr(9).$kp%$iKeyLength.chr(10);

? ? ? ? ? ? $dp = ($n +$step) %$iDicLength;

$o? .=$aDic[$dp];

$kp++;

}

return $o;

}

private static function ctn($c)

{

$aDic = str_split(self::DIC);

$aMap = array_flip($aDic);

return isset($aMap[$c]) ?$aMap[$c] :'|';

}