Reload Table

Hi, i need u help again
i need reload my table after click on btn #refresh, but this not workong(

var table;
function main_table() {
  $(document).ready(function () {
        table = $('#example').DataTable({
            ajax: {
                url: '/project/all_items/',
                dataSrc: ''

            },
            "sScrollY": "90vh",
            "bPaginate": true,
            "aoColumns": [
                ...
            ],


        });
}

function refresh() {
    $('#refresh').click( function() {
        table.ajax.reload();
}