xrLabel15.DataBindings.Add("Text", ds, "R1.Amount");//绑定小计(当前单据的总金额)

xrLabel23.DataBindings.Add("Text", ds, "R1.Amount");//绑定总计(所有单据的总金额)

   private void button3_Click(object sender, EventArgs e)

        {

            XtraReport_MasterDetail mMyReport = new XtraReport_MasterDetail(); //报表实例

            DataSet data = DAL.GetMasterDetailData();//取销售订单主从表数据

            mMyReport.SetReportDataSource(data);//绑定报表的数据源

            //打开报表预览窗体

            frmReportPreview.DoPreviewReport(mMyReport, this);

        }

        /// <summary>

        /// 设置主从表的数据源

        /// </summary>

        /// <param name="reportData"></param>

        public void SetReportDataSource(DataSet reportData)

        {

            //因涉及到修改DataSet的内部属性，建议创建副本进行操作。

            DataSet ds = reportData.Copy();//创建副本

            //重要！！！给组(GroupHeader)绑定主键字段

            //本报表是按业务单号分组

            GroupField gf = new GroupField("SONO", XRColumnSortOrder.Ascending);

            GroupHeader1.GroupFields.Add(gf);

            //给数据集建立主外键关系

            DataColumn parentColumn = ds.Tables["tb_SO"].Columns["SONO"];

            DataColumn childColumn = ds.Tables["tb_SOs"].Columns["SONO"];

            DataRelation R1 = new DataRelation("R1", parentColumn, childColumn);

            ds.Relations.Add(R1);

            //绑定主表的数据源

            this.DataMember = "tb_SO";

            this.DataSource = ds;

            //绑定明细表的数据源

            this.DetailReport.DataMember = "R1";

            this.DetailReport.DataSource = ds;

//自动绑定明细表XRLabel的数据源

            this.BindingFields(ds, this.Detail1.Controls);

            xrLabel15.DataBindings.Add("Text", ds, "R1.Amount");//绑定小计(当前单据的总金额)

            xrLabel23.DataBindings.Add("Text", ds, "R1.Amount");//绑定总计(所有单据的总金额)

        }