public partial class FrmMain : Form
{
    // 起始时间以毫秒为单位
    int tickStart = 0;

    public FrmMain()
    {
        InitializeComponent();
    }

    private void Form1_Load( object sender, EventArgs e )
    {
        //获取引用
        GraphPane myPane = zedGraphControl1.GraphPane;
        //设置标题
        myPane.Title.Text = "实时曲线";
        //设置X轴说明文字
        myPane.XAxis.Title.Text = "时间";
        //设置Y轴说明文字
        myPane.YAxis.Title.Text = "温度";

        //设置1200个点,假设每50毫秒更新一次,刚好检测1分钟,一旦构造后将不能更改这个值
        RollingPointPairList list = new RollingPointPairList( 1200 );

        //开始，增加的线是没有数据点的(也就是list为空)
        //增加一条名称:Voltage，颜色Color.Bule，无符号，无数据的空线条
        LineItem curve = myPane.AddCurve("温度", list, Color.Blue, SymbolType.None);

        timeDraw.Interval = 10;        //设置timer控件的间隔为50毫秒
        timeDraw.Enabled = true;    //timer可用
        timeDraw.Start();            //开始

        myPane.XAxis.Scale.Min = 0;        //X轴最小值0
        myPane.XAxis.Scale.Max = 30;    //X轴最大30
        myPane.XAxis.Scale.MinorStep = 1;//X轴小步长1,也就是小间隔
        myPane.XAxis.Scale.MajorStep = 5;//X轴大步长为5，也就是显示文字的大间隔

        //改变轴的刻度
        zedGraphControl1.AxisChange();

        //保存开始时间
        tickStart = Environment.TickCount;
    }

    private void timer1_Tick( object sender, EventArgs e )
    {
        //确保CurveList不为空
        if (zedGraphControl1.GraphPane.CurveList.Count <= 0)
        {
            return; 
        }

        //取Graph第一个曲线，也就是第一步:在GraphPane.CurveList集合中查找CurveItem
        LineItem curve = zedGraphControl1.GraphPane.CurveList[0] as LineItem;
        if (curve == null)
        {
            return;
        }

        //第二步:在CurveItem中访问PointPairList(或者其它的IPointList)，根据自己的需要增加新数据或修改已存在的数据
        IPointListEdit list = curve.Points as IPointListEdit;

        if (list == null)
        {
            return;
        }

        // 时间用秒表示
        double time = ( Environment.TickCount - tickStart ) / 1000.0;
        // 3秒循环
        list.Add( time, Math.Sin( 2.0 * Math.PI * time / 3.0 ) );

        Scale xScale = zedGraphControl1.GraphPane.XAxis.Scale;
        if ( time > xScale.Max - xScale.MajorStep )
        {
            xScale.Max = time + xScale.MajorStep;
            xScale.Min = xScale.Max - 30.0;
        }

        //第三步:调用ZedGraphControl.AxisChange()方法更新X和Y轴的范围
        zedGraphControl1.AxisChange();

        //第四步:调用Form.Invalidate()方法更新图表
        zedGraphControl1.Invalidate();
    }

    private void Form1_Resize( object sender, EventArgs e )
    {
        SetSize();
    }

    private void SetSize()
    {
        // 控制始终是以10像素插入矩形从客户端的形
        Rectangle formRect = this.ClientRectangle;
        formRect.Inflate( -10, -10 );

        if ( zedGraphControl1.Size != formRect.Size )
        {
            zedGraphControl1.Location = formRect.Location;
            zedGraphControl1.Size = formRect.Size;
        }
    }