private void Button2_Click(object sender, EventArgs e)

        {

            DataTable table = new DataTable();

            this.chart1.Series.Clear();   //清空图表中的内容

            this.chart1.Titles.Add("Total Income");//添加标题

            chart1.DataSource = table;

            Series series = this.chart1.Series.Add("LSL");//添加第一个表

            series.XValueMember = "Date";  //x轴为时间

            series.YValueMembers = "LSL";  //y轴为数据

            Series series1 = this.chart1.Series.Add("USL");//添加第二个表

            series1.XValueMember = "Date";

            series1.YValueMembers = "USL";

            this.chart1.Series[].ChartType= SeriesChartType.Spline;//指定图表的类型，这里是折线图

            this.chart1.Series[].Color = Color.Blue;

            this.chart1.Series[].ChartType = SeriesChartType.Spline;

            this.chart1.Series[].Color = Color.Red;

        }