Load JQGrid On Button Click Everytime

script tag

    var firstClick = true;
    $(document).ready(function () {
        $('.editor-date > input').datepicker();
        $('.getdata').click(function () {
            if (!firstClick) {
                $("#GridTable").trigger("reloadGrid");
            }
                firstClick = false;
                $('#GridTable').jqGrid({
                    url: '<%= Url.Action("GetData", "Report") %>',
                    datatype: 'json',
                    mtype: 'POST',
                    colNames: ['Log ID'],
                    colModel: [{ name: 'LogID', index: 'MessageLogID', key: true, formatter: pointercursor }],
                    multiselect: true,
                    sortname: 'LogID',
                    sortorder: "asc",
                    viewrecords: true,
                    pager: $('#pager'),
                    rowNum: 20,
                    rowList: [5, 10, 20, 50],
                   postData: {
                        IdParam: function () {
                            return $('#testLogID').val();
                        }
                    },
                    jsonReader: {
                        repeatitems: false,
                        id: 'LogID',
                        records: 'TotalRecords',
                        total: 'TotalPages',
                        page: 'CurrentPage',
                        root: 'Rows'
                    },
                    loadError: function (xhr, status, error) {
                        messageBox('Error', 'Error occurred loading data.');
                    },
                    height: 'auto',
                    width: 'auto'
                });

            });

script end tag