Parse months and years from a string

parseExpirationDate.js

function parseExpirationDate(string)
{
    var components = string.split(/\b/);
    var index = components.length;
    var month, year;

    // first we parse the words (so that month names can appear in any order)
    while (index--) {
        if (isNaN(parseInt(components[index]))) {
            var candidateMonth = (new Date(components[index]+" 1, 2000")).getMonth();
            if (!isNaN(candidateMonth)) {
                month = candidateMonth + 1;
            }

            components.splice(index, 1);
        }
    }

    // then we parse numbers
    index = components.length;
    while (index--) {
        var string = components[index];
        var number = parseInt(string);
        if (string.length > 2 || number > 12) {
            year = number;
        } else if (year === undefined) {
            year = number;
        } else {
            month = number;
        }
    }

    if (year < 100)
        year += Math.floor(new Date().getFullYear()/100)*100;

    return  {
        month: month,
        year: year,
        success: !isNaN(new Date(["01", month || "_", year || "_"].join("/")).getTime())
    }
}