Decimal to roman numeral converter in php

Php program for Decimal to roman numeral converter. Here mentioned other language solution.

<?php 
//  Php program for
//  Conversion from Decimal to roman number
class Perform
{
    // Display roman value of n
    function result($n)
    {
        switch ($n) {
            // Test Cases
            case 1:
                echo "I";
                break;
            case 4:
                echo "IV";
                break;
            case 5:
                echo "V";
                break;
            case 9:
                echo "IX";
                break;
            case 10:
                echo "X";
                break;
            case 40:
                echo "XL";
                break;
            case 50:
                echo "L";
                break;
            case 90:
                echo "XC";
                break;
            case 100:
                echo "C";
                break;
            case 400:
                echo "CD";
                break;
            case 500:
                echo "D";
                break;
            case 900:
                echo "DM";
                break;
            case 1000:
                echo "M";
                break;
        }
    }
    function select($number, &$collection, $size)
    {
        $n = 1;
        $i = 0;
        for (
        $i = 0; $i < $size; ++$i)
        {
            if ($number >= $collection[$i])
            {
                $n = $collection[$i];
            }
            else
            {
                break;
            }
        }
        Perform::result($n);
        // Reduce the value of number
        return $number - $n;
    }
    function romanNo($number)
    {
        if ($number <= 0)
        {
            // When is not a natural number
            return;
        }
        // Base case collection
        $collection = array(
            1, 4, 5, 9, 10, 40, 50, 90, 100, 400, 500, 900, 1000
        );
        // Get the size of collection
        $size = count($collection);
        echo " " . $number . " : ";
        while ($number > 0)
        {
            $number = Perform::select($number, $collection, $size);
        }
        // Add new line
        print("\n");
    }

}
function main()
{
    // Test Case
    Perform::romanNo(10);
    Perform::romanNo(18);
    Perform::romanNo(189);
    Perform::romanNo(604);
    Perform::romanNo(982);
    Perform::romanNo(3000);
}
main();

Output

 10 : X
 18 : XVIII
 189 : CLXXXIX
 604 : DCIV
 982 : DMLXXXII
 3000 : MMM