owchart证券图形控件学习：如何添加趋势线?

源码：

public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();

            Chart chart = new Chart();  //创建K线
            chart.Dock = DockStyle.Fill;  //设置填充          
            Controls.Add(chart);   //添加控件

            //设置显示左轴的宽度
            chart.LeftYScaleWidth = 100; 
            //设置K线的间隔   
            chart.XScalePixel = 20;  
            //添加第一个层，占100%   
            ChartDiv div1 = chart.AddChartDiv(100); 

            //声明线的字段   
            int lineFiled = 4; 

            //添加K线   
            LineShape barShape = chart.AddLine("趋势线", lineFiled, div1);
            
            //获取数据源 
            CTableEx dataSource = chart.DataSource;

            //启动循环50次    
            DateTime dateTime = DateTime.Now;  
            for (int i = 0; i < 50; i++)
            {
                //获取时间 
                double date = LbCommon.getDateNum(dateTime.Year, dateTime.Month, dateTime.Day, 0, 0, 0, 0);     
                dataSource.Set(date, 4, i);                
                dateTime = dateTime.AddDays(1);           
            }

            //刷新图像  
            chart.RefreshGraph();
        }

    }

界面：