numbers_0_999.js

var number;
var chaineFinale;
var numberList = {
	0: 'zéro',
	1: 'un',
	2: 'deux',
	3: 'trois',
	4: 'quatre',
	5: 'cinq',
	6: 'six',
	7: 'sept',
	8: 'huit',
	9: 'neuf',
	10: 'dix',
	11: 'onze',
	12: 'douze',
	13: 'treize',
	14: 'quatorze',
	15: 'quinze',
	16: 'seize',
	20: 'vingt',
	30: 'trente',
	40: 'quarante',
	50: 'cinquante',
	60: 'soixante',
	80: 'quatre-vingt',
	100: 'cent'
};

while (!(number = prompt("Saisissez un nombre compris entre 0 et 999")) || (number < 0 && number > 999)) {}

number = parseInt(number, 10);

var fullNumber = (function (num) {
    
    var splittedNumber = {
        unite: 0,
        dizaine: 0,
        centaine: 0
    };
    var letterNumber = {
    	unite: '',
    	dizaine: '',
    	centaine: ''
    };
    
    if (typeof num != 'number' || isNaN(num)) {
        return splittedNumber;
    }
    
    splittedNumber.unite = num % 10;
    
    num = (num - splittedNumber.unite) / 10;
    
    splittedNumber.dizaine = num % 10;
    
    num = (num - splittedNumber.dizaine) / 10;
    
    splittedNumber.centaine = num;
    
    switch (splittedNumber.centaine) {
	case 0:
		break;
	case 1:
		letterNumber.centaine = numberList[100];
		break;
	default:
		letterNumber.centaine = numberList[splittedNumber.centaine] + '-' + numberList[100];
		break;
	}
    if ((splittedNumber.dizaine == 1 || splittedNumber.dizaine == 7 || splittedNumber.dizaine == 9) && splittedNumber.unite < 7) {
    	
    	var sup = splittedNumber.dizaine * 10 + splittedNumber.unite;
    	
    	if (splittedNumber.dizaine != 1) {
    		var minus = (splittedNumber.dizaine - 1) * 10
    		
    		letterNumber.dizaine = numberList[minus];
    		sup -= minus;
    	}
    	if (splittedNumber.dizaine == 7 && splittedNumber.unite == 1) {
    		letterNumber.unite = 'et-';
    	}
    	
    	letterNumber.unite += numberList[sup];
    	
    }
    else {
    	switch (splittedNumber.dizaine) {
		case 0:
			break;
		case 7:
		case 9:
			letterNumber.dizaine = numberList[(splittedNumber.dizaine - 1) * 10] + '-' + numberList[10];
			break;
		default:
			letterNumber.dizaine = numberList[splittedNumber.dizaine * 10];
			break;
		}
    	switch (splittedNumber.unite) {
		case 0:
			if (splittedNumber.dizaine == 8) {
				letterNumber.dizaine += 's';
			}
			break;
		case 1:
			if (splittedNumber.dizaine != 0 && splittedNumber.dizaine < 8) {
				letterNumber.unite = 'et-';
			}
		default:
			letterNumber.unite += numberList[splittedNumber.unite];
			break;
		}
    	
    	if (splittedNumber.centaine > 1 && splittedNumber.dizaine == 0 && splittedNumber.unite == 0) {
    		letterNumber.centaine += 's';
    	}
    	
    }
    
    return letterNumber;
    
})(number);

var numberArray = [];

if (fullNumber.centaine) {
	numberArray.push(fullNumber.centaine);
}
if (fullNumber.dizaine) {
	numberArray.push(fullNumber.dizaine);
}
if (fullNumber.unite) {
	numberArray.push(fullNumber.unite);
}

if (numberArray.length == 0) {
	numberArray.push(numberList[0]);
}

alert(numberArray.join('-'));