Terbilang - Konversi bilangan menjadi kalimat dalam Bahasa Indonesia

Number.php

<?php

class Number
{
    function spell($number)
    {
        $words = array(
            "", "Satu", "Dua", "Tiga", "Empat", "Lima", "Enam", "Tujuh",
            "Delapan", "Sembilan", "Sepuluh", "Sebelas"
        );

        switch($number)
        {
            case $number < 12:
                return trim($words[$number]);
                break;
            case $number < 20;
                return trim($this->spell($number - 10) . " Belas");
                break;
            case $number < 100:
                return trim($this->spell($number / 10) . " Puluh " . $this->spell($number % 10));
                break;
            case $number < 200:
                return trim("Seratus " . $this->spell($number - 100));
                break;
            case $number < 1000:
                return trim($this->spell($number / 100) . " Ratus " . $this->spell($number % 100));
                break;
            case $number < 2000:
                return trim("Seribu " . $this->spell($number - 1000));
                break;
            case $number < 1000000:
                return trim($this->spell($number / 1000) . " Ribu " . $this->spell($number % 1000));
                break;
            case $number < 1000000000:
                return trim($this->spell($number / 1000000) . " Juta " . $this->spell($number % 1000000));
                break;
            case $number < 1000000000000:
                return trim($this->spell($number / 1000000000) . " Milyar " . $this->spell($number % 1000000000));
        }
    }
}

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