PHP加密算法转换delphi出问题

 function encrypt($string,$operation,$key='')    {        $key=md5($key);        $key_length=strlen($key);        $string=$operation=='d'?base64_decode($string):substr(md5($string.$key),0,8).$string;        $string_length=strlen($string);        $rndkey=$box=array();        $result='';        for($i=0;$i<=255;$i++)        {            $rndkey[$i]=ord($key[$i%$key_length]);            $box[$i]=$i;        }        for($j=$i=0;$i<256;$i++)        {            $j=($j+$box[$i]+$rndkey[$i])%256;            $tmp=$box[$i];            $box[$i]=$box[$j];            $box[$j]=$tmp;        }        for($a=$j=$i=0;$i<$string_length;$i++)        {            $a=($a+1)%256;            $j=($j+$box[$a])%256;            $tmp=$box[$a];            $box[$a]=$box[$j];            $box[$j]=$tmp;            $result.=chr(ord($string[$i])^($box[($box[$a]+$box[$j])%256]));        }        if($operation=='d')        {            if(substr($result,0,8)==substr(md5(substr($result,8).$key),0,8))            {                return substr($result,8);            }            else            {                return'';            }        }        else        {            return str_replace('=','',base64_encode($result));        }    }$id = '123sdfsdf';$key = 'aasd1234567985fdgdfdfgdg';$token = encrypt($id, 'e', $key);echo '加密:'.encrypt($id, 'e', $key);echo '<br />';echo '解密：'.encrypt($token, 'd', $key);

function encrypt(str, operation, key: string): string;  function strtomd5(s: string): string;  var    md5encode: tidhashmessagedigest5;  begin         md5encode := tidhashmessagedigest5.create;    result := md5encode.ashex(md5encode.hashvalue(s));    md5encode.free;       end;var  key_length: integer;  string_length: integer;  i, j, a: integer;  rndkey: array[0..255] of byte;  box: array[0..255] of byte;  tmp: byte;begin  key := lowercase(strtomd5(key));  key_length := length(key);  if operation = 'd' then    str := decodestring(str)  else    str := copy(lowercase(strtomd5(str + key)), 1, 8) + str;  string_length := length(str);  result := '';  for i := 0 to 255 do  begin    rndkey[i] := ord(key[(i mod key_length) + 1]);    box[i] := i;  end;  j := 0;  for i := 0 to 255 do  begin    j := (j + box[i] + rndkey[i]) mod 256;    tmp := box[i];    box[i] := box[j];    box[j] := tmp;  end;  a := 0;  j := 0;  for i := 1 to string_length do  begin    a := (a + 1) mod 256;    j := (j + box[a]) mod 256;    tmp := box[a];    box[a] := box[j];    box[j] := tmp;    result := result + chr(ord(str[i]) xor (box[(box[a] + box[j]) mod 256]));  end;  if (operation = 'd') then  begin      if (copy(result, 1, 8) = copy(lowercase(strtomd5(copy(result, 9, length(result) - 8) + key)), 1, 8)) then    begin      result := copy(result, 9, length(result) - 8);    end    else    begin      result := '';    end;  end  else  begin    result := stringreplace(encodestring(result), '=', '', [rfreplaceall]);  end; end;