I'm trying to fill selects with json data from a web service. I'm getting error 'Object doesn't support this property or method.' when I do this $(this).html(options.join'')); Any ideas what I'm doing wrong?

;(function($) {

    $.fillSelect = {};

    $.fn.fillSelect = function(url, map) {
        var jsonpUrl = url + "?callback=?";        

 $.getJSON(jsonpUrl,
function(d) {

                    var options = [];
                    var txt = map[0];
                    var val = map[1];


               options.push('<option>--Select--</option>');
    $.each(d, function(index, item) {
        options.push('<option value="' + item[val] + '">' + item[txt] + '</option>');
    });

    $(this).html(options.join('')); //getting error  Object doesn't support this property or method
}


    };
})(jQuery);