JavaScript numbers to Words

Question

I\'m trying to convert numbers into english words, for example 1234 would become: \"one thousand two hundred thirty four\".

My Tact

Answer 1

Here, I wrote an alternative solution:

1) The object containing the string constants:

var NUMBER2TEXT = {
    ones: ['', 'one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine', 'ten', 'eleven', 'twelve', 'thirteen', 'fourteen', 'fifteen', 'sixteen', 'seventeen', 'eighteen', 'nineteen'],
    tens: ['', '', 'twenty', 'thirty', 'fourty', 'fifty', 'sixty', 'seventy', 'eighty', 'ninety'],
    sep: ['', ' thousand ', ' million ', ' billion ', ' trillion ', ' quadrillion ', ' quintillion ', ' sextillion ']
};

2) The actual code:

(function( ones, tens, sep ) {

    var input = document.getElementById( 'input' ),
        output = document.getElementById( 'output' );

    input.onkeyup = function() {
        var val = this.value,
            arr = [],
            str = '',
            i = 0;

        if ( val.length === 0 ) {
            output.textContent = 'Please type a number into the text-box.';
            return;  
        }

        val = parseInt( val, 10 );
        if ( isNaN( val ) ) {
            output.textContent = 'Invalid input.';
            return;   
        }

        while ( val ) {
            arr.push( val % 1000 );
            val = parseInt( val / 1000, 10 );   
        }

        while ( arr.length ) {
            str = (function( a ) {
                var x = Math.floor( a / 100 ),
                    y = Math.floor( a / 10 ) % 10,
                    z = a % 10;

                return ( x > 0 ? ones[x] + ' hundred ' : '' ) +
                       ( y >= 2 ? tens[y] + ' ' + ones[z] : ones[10*y + z] );
            })( arr.shift() ) + sep[i++] + str;
        }

        output.textContent = str;
    };

})( NUMBER2TEXT.ones, NUMBER2TEXT.tens, NUMBER2TEXT.sep );

Live demo: http://jsfiddle.net/j5kdG/