My Multiple Date Selector

Custom Multiple Date picker on jQuery UI Datepicker.

HTML

<div id="datepicker"></div>

CSS

.ui-state-highlight{
    background:red;
}
.ui-highlight .ui-state-default{
    background: red !important;
    border-color: red !important;
    color: white !important;
}

JavaScript

// Maintain array of dates
var dates = new Array();

function addDate(date) {
    if (jQuery.inArray(date, dates) < 0) 
        dates.push(date);
}


// Adds a date if we don't have it yet, else remove it
function addOrRemoveDate(date) {
    var index = jQuery.inArray(date, dates);
    if (index >= 0) 
        removeDate(index);
    else 
        addDate(date);
}

// Takes a 1-digit number and inserts a zero before it
function padNumber(number) {
    var ret = new String(number);
    if (ret.length == 1) 
        ret = "0" + ret;
    return ret;
}

jQuery(function () {
    jQuery("#datepicker").datepicker({
        onSelect: function (dateText, inst) {
            addOrRemoveDate(dateText);
        },
        beforeShowDay: function (date) {
            var year = date.getFullYear();
            // months and days are inserted into the array in the form, e.g "01/01/2009", but here the format is "1/1/2009"
            var month = padNumber(date.getMonth() + 1);
            var day = padNumber(date.getDate());
            // This depends on the datepicker's date format
            var dateString = month + "/" + day + "/" + year;

            var gotDate = jQuery.inArray(dateString, dates);
            if (gotDate >= 0) {
                // Enable date so it can be deselected. Set style to be highlighted
                return [true, "ui-state-highlight"];
            }
            // Dates not in the array are left enabled, but with no extra style
            return [true, ""];
        }
    });
});