php - 用php将数字转换为罗马数字

Question

我需要用 php 将普通数字转换为罗马数字，我有以下代码:

        <?php

function roman2number($roman){
    $conv = array(
        array("letter" => 'I', "number" => 1),
        array("letter" => 'V', "number" => 5),
        array("letter" => 'X', "number" => 10),
        array("letter" => 'L', "number" => 50),
        array("letter" => 'C', "number" => 100),
        array("letter" => 'D', "number" => 500),
        array("letter" => 'M', "number" => 1000),
        array("letter" => 0, "number" => 0)
    );
    $arabic = 0;
    $state = 0;
    $sidx = 0;
    $len = strlen($roman);

    while ($len >= 0) {
        $i = 0;
        $sidx = $len;

        while ($conv[$i]['number'] > 0) {
            if (strtoupper(@$roman[$sidx]) == $conv[$i]['letter']) {
                if ($state > $conv[$i]['number']) {
                    $arabic -= $conv[$i]['number'];
                } else {
                    $arabic += $conv[$i]['number'];
                    $state = $conv[$i]['number'];
                }
            }
            $i++;
        }

        $len--;
    }

    return($arabic);
}


function number2roman($num,$isUpper=true) {
    $n = intval($num);
    $res = '';

    /*** roman_numerals array ***/
    $roman_numerals = array(
        'M' => 1000,
        'CM' => 900,
        'D' => 500,
        'CD' => 400,
        'C' => 100,
        'XC' => 90,
        'L' => 50,
        'XL' => 40,
        'X' => 10,
        'IX' => 9,
        'V' => 5,
        'IV' => 4,
        'I' => 1
    );

    foreach ($roman_numerals as $roman => $number)
    {
        /*** divide to get matches ***/
        $matches = intval($n / $number);

        /*** assign the roman char * $matches ***/
        $res .= str_repeat($roman, $matches);

        /*** substract from the number ***/
        $n = $n % $number;
    }

    /*** return the res ***/
    if($isUpper) return $res;
    else return strtolower($res);
}

/* TEST */
echo $s=number2roman(6,true);
echo "\n and bacK:\n";
echo roman2number($s);


?>

尝试这种方式但不起作用:

echo $s=number2roman((.$row['id'].),true);
echo "\n and bacK:\n";
echo roman2number($s);

问题是我需要更改数字是我的 sql 数据库的读数，但不知道如何更改。

Answer 1

我在这里找到了这段代码:http://php.net/manual/en/function.base-convert.php

优化美化功能:

/**
 * @param int $number
 * @return string
 */
function numberToRomanRepresentation($number) {
    $map = array('M' => 1000, 'CM' => 900, 'D' => 500, 'CD' => 400, 'C' => 100, 'XC' => 90, 'L' => 50, 'XL' => 40, 'X' => 10, 'IX' => 9, 'V' => 5, 'IV' => 4, 'I' => 1);
    $returnValue = '';
    while ($number > 0) {
        foreach ($map as $roman => $int) {
            if($number >= $int) {
                $number -= $int;
                $returnValue .= $roman;
                break;
            }
        }
    }
    return $returnValue;
}