private void pageChanged()
        {
            try
            {
                System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.WaitCursor;
                //
                BLL.IRep单品汇总表 bll = new BLL.Rep单品汇总表();
                var           dt  = bll.GetData(key, pageSize, pageIndex, out total, "编号", "单数,数量,金额");
                //
                dt_excel = dt;
                this.dg_data.DataSource = dt;

                int n = pageIndex;
                int m = (int)Math.Ceiling((decimal)this.total / (decimal)this.pageSize);
                this.pageCount   = m;
                this.Label1.Text = string.Format("第{0}页,共{1}页", n.ToString(), m.ToString());
            }
            catch (Exception e)
            {
                Program.frmMsg(e.Message);
            }
            finally
            {
                System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.Default;
            }
        }
        private void btn_export_Click(object sender, EventArgs e)
        {
            var f = new SaveFileDialog();

            f.Filter = "*.xls|*.xls";
            if (dt_excel == null)
            {
                MessageBox.Show("请先查询再导出!");
            }
            else if (f.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                BLL.IRep单品汇总表 bll = new BLL.Rep单品汇总表();
                dt_excel = bll.GetData(key, 10000, 1, out total, "编号", "单数,数量,金额");
                ToExcel.toExcel(dt_excel, f.FileName);
            }
        }