将在图表控件上绘制的点写入文本文件，但每个坐标只能写入一次

按钮点击事件:

private void chart1_MouseClick(object sender, MouseEventArgs e)
{
    if (outofrange == false)
    {
        valuePoints.Add(new PointF(X, Y));
        paintToCalaculate = true;
        if (X > 0 && Y > 0)
        {
            chart1.Invalidate();
            SavePointsCoordinates();
        }
    }
}

和SavePointsCoordinates方法:

StreamWriter w;
int countPoints = 0;
private void SavePointsCoordinates()
{
    if (drawPoints.Count > 0)
    {
        foreach (Point p in drawPoints)
        {
            countPoints++;
            w = new StreamWriter(@"c:'chart'chartData.txt",true);
            w.WriteLine("Point " + countPoints + "X = " + p.X + " Y = " + p.Y);
        }
        w.Close();
    }
}

问题是，如果我将点击按钮不止一次没有添加新的点，它将继续添加到文本文件相同的坐标。

实际上，它已经将相同的点坐标添加到按钮单击事件中的valuePoints中。valuePoints是List

drawPoints是我在chart1 paint事件中使用的List:

Pen pen = new Pen(Color.Blue, 2.5f);
SolidBrush myBrush = new SolidBrush(Color.Red);
private void chart1_Paint(object sender, PaintEventArgs e)
{
    if (paintToCalaculate)
    {
        Series s = chart1.Series.FindByName("dummy");
        if (s == null)
        {
            s = chart1.Series.Add("dummy");
        }
        drawPoints.Clear();
        s.Points.Clear();
        foreach (PointF p in valuePoints)
        {
            s.Points.AddXY(p.X, p.Y);
            DataPoint pt = s.Points[0];
            double x = chart1.ChartAreas[0].AxisX.ValueToPixelPosition(pt.XValue);
            double y = chart1.ChartAreas[0].AxisY.ValueToPixelPosition(pt.YValues[0]);
            drawPoints.Add(new Point((int)x, (int)y));
            s.Points.Clear();
        }
        paintToCalaculate = false;
        chart1.Series.Remove(s);
    }
    foreach (Point p in drawPoints)
    {
        e.Graphics.FillEllipse(Brushes.Red, p.X - 2, p.Y - 2, 4, 4);
    }
    if (drawPoints.Count > 1)
    {
        e.Graphics.DrawLines(pen, drawPoints.ToArray());
    }
}

我想做的是将我在图表上绘制的所有点坐标写入文本文件，然后在构造函数中读取文本文件，将这些点绘制回图表，并绘制它们之间的线。

我不确定我画的点和线之间的顺序是否有意义。只需将所有坐标写入文本文件并读取

string yourPointsFile = "d:''myPoints.xml";
XmlSerializer xmls = new XmlSerializer(typeof(List<Point>));
// save the points maybe when closing the program:
using (Stream writer = new FileStream(yourPointsFile, FileMode.Create))
{
    xmls.Serialize(writer, points);
    writer.Close();
}
// load the points at startup:
using (Stream reader = new FileStream(yourPointsFile, FileMode.Open))
{
    points = xmls.Deserialize(reader);
    reader.Close();
}

if (!points.Contains(somePoint) ) points.Add(somePoint);