Sonarr/NzbDrone.Web/_backboneApp/Shared/AutoComplete.js

$.fn.folderAutoComplete = function () {
    $(this).typeahead({
        source: function (query, process) {
            $.ajax({
                url: '/api/directories',
                dataType: "json",
                type: "POST",
                data: { query: query },
                success: function (data) {
                    process(data);
                }
            });
        },
        minLength: 3
    });
}