Bootstrap Table 判斷是否選中行，沒選中給出提示

//#region 返回選中行數據

function getSelectedRowsData(selector) {
    ///<summary>返回選中行數據</summary>
    ///<param name="selector">Bootstrap Table 表對象</param>

    return $.map(selector.bootstrapTable("getSelections"),
        function(row) {
            return row; // 返回選中行數據
        });
}

//#endregion

   // 刪除
    $("#btnBatchDelete").on("click",
        function() {
            var selectedRows = getSelectedRowsData($("#tableTop"));

            if (selectedRows.length === 0) {
                toastr.warning("請選擇要刪除的數據!");
                return;
            } else {
                toastr.warning(selectedRows.length);

                var idArray = [];
                for (var i = 0; i < selectedRows.length; i++) {
                    idArray.push(selectedRows[i].BookId);
                }

                // 彈窗 確認
                swal({
                        title: "溫馨提示",
                        text: "您確認要刪除圖書ID：" + idArray + "嗎？",
                        icon: "warning",
                        buttons: true,
                        dangerMode: true,
                    })
                    .then((willDelete) => {
                        if (willDelete) {

                            // 刪除操作邏輯實現
                            toastr.success("刪除操作執行中！");

                            window.swal("刪除成功！", { icon: "success" });

                            // 刷新數據
                            window.swal("刷新數據成功！", { icon: "success" });

                        } else {
                            
                        }
                    });
            }
        });