Question

我正在尝试创建一个在特定顶点之间绘制一些边的图形。我的想法是创建随机顶点，并指定“发射功率”整数。它的工作方式是，如果两个节点之间的距离小于或等于发射功率，则会在它们之间划出一条线。

我正在使用MSDN图表控件来执行此操作。虽然有线条绘制的问题。我不断收到以下错误消息：

Error   2   Argument 2: cannot convert from 'System.Windows.Forms.DataVisualization.Charting.DataPoint' to 'System.Drawing.Point'

试图破解这个，所以我想登录到这里，看看是否有其他人可能知道该怎么做。我找不到有关如何转换它的任何内容。

以下是一些代码示例：

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

    public void createNodes(int x, int y, int Nodes, int dgNodes)
    {
        Random rdn = new Random();

        for (int i = 0; i < (Nodes - dgNodes); i++)
        {
            chtGraph.Series["NoDG"].Points.AddXY
                        (rdn.Next(x), rdn.Next(y));
        }

        for (int i = 0; i <= dgNodes - 1; i++)
        {
            chtGraph.Series["DG"].Points.AddXY
                        (rdn.Next(x), rdn.Next(y));
        }
    }

    public void buildGraph(int x, int y, int Nodes, int dgNodes)
    {
        //set the min/max axis on the chart
        chtGraph.ChartAreas["ChartArea1"].AxisX.Maximum = x;
        chtGraph.ChartAreas["ChartArea1"].AxisX.Minimum = 0;
        chtGraph.ChartAreas["ChartArea1"].AxisY.Maximum = y;
        chtGraph.ChartAreas["ChartArea1"].AxisY.Minimum = 0;
        chtGraph.ChartAreas["ChartArea1"].AxisX.Interval = x / 10;
        chtGraph.ChartAreas["ChartArea1"].AxisY.Interval = y / 10;

        chtGraph.ChartAreas["ChartArea1"].AxisX.MajorGrid.Enabled = false;
        chtGraph.ChartAreas["ChartArea1"].AxisY.MajorGrid.Enabled = false;

        //build all the nodes
        createNodes(x, y, Nodes, dgNodes);
    }

    public void drawEdges(int intNumNodes, int intTransPower)
    {
        ChartGraphics gr = new ChartGraphics();
        Pen pen = new Pen(Color.Black, 1);
        //System.Drawing.Point[] pts = new Point[4];
        //pts[0] = new Point(20, 20);
        //pts[1] = new Point(20, 140);
        //pts[2] = new Point(60, 60);
        //pts[3] = new Point(180, 80);
        //gr.DrawLine(pen, pts[1], pts[2]);

        DataPoint[] pts = new DataPoint[intNumNodes];
        int i = 0;

        //Gather all the data points into an array
        foreach (DataPoint p in chtGraph.Series[0].Points)
        {
            pts[i] = p;
            i++;
        }

        i = 0;

        //loop through all the data points
        foreach (DataPoint p in pts)
        {
            //examine all the other data points for each data point visited
            for (int j = 0; j < pts.Length; j++)
            {
                //convert the y values
                int yval = Convert.ToInt32(p.YValues[0]);
                int yValNeighbors = Convert.ToInt32(pts[j].YValues[0]);

                //if the distance from the parent node (p) to the neighbor node is less than the transmit power, then draw a line
                if (Math.Sqrt(Math.Pow((p.XValue - pts[j].XValue), 2) + Math.Pow((yval - yValNeighbors), 2)) <= intTransPower)
                {
                    gr.Graphics.DrawLine(pen, p, pts[j);
                }
            }
        }
    }

    private void btnExecute_Click(object sender, EventArgs e)
    {
        if (txtDG.Text == "" || txtNodes.Text == "" || txtStorage.Text == "" || txtTransPower.Text == ""
            || txtXAxis.Text == "" || txtXAxis.Text == "")
        {
            lblError.Text = "Please enter in all inputs!";
            lblError.Visible = true;
            return;
        }
        //create variables for use through program

        int intTransPower = Convert.ToInt32(txtTransPower.Text);
        int intXAxis = Convert.ToInt32(txtXAxis.Text);
        int intYAxis = Convert.ToInt32(txtYAxis.Text);
        int intNum_DG = Convert.ToInt32(txtDG.Text);
        int intNumNodes = Convert.ToInt32(txtNodes.Text);
        int intStorage = Convert.ToInt32(txtStorage.Text);

        lblError.Visible = false;
        lblError.Text = "";

        if (txtDG.Text == "" || txtNodes.Text == "" || txtStorage.Text == "" || txtTransPower.Text == "" 
            || txtXAxis.Text == "" || txtXAxis.Text == "")
        {
            lblError.Text = "Please enter in all inputs!";
            lblError.Visible = true;}

            chtGraph.Series["NoDG"].Points.Clear();
            chtGraph.Series["DG"].Points.Clear();
            buildGraph(intXAxis, intYAxis, intNumNodes, intNum_DG);
            drawEdges(intNumNodes, intTransPower);
        }
    }
}

Answer 1

DataPoint和Point根本不是同一类型。但是，您可以将DataPoint字段复制到Point中。粗略的例子：

Point point = new Point ();
DataPoint dataPoint = new DataPoint() ;
.....
point.X = dataPoint.X ;
point.Y = dataPoint.Y ;

Answer 2

如果我弄错了，请原谅我，但DataPoint不是Point的子类。它们无法自动转换为System.Drawing.Point。为什么不创建新积分？

//if the distance from the parent node (p) to the neighbor node is less than the transmit power, then draw 
if (Math.Sqrt(Math.Pow((p.XValue - pts[j].XValue), 2) + Math.Pow((yval - yValNeighbors), 2)) <= intTransPower)
{
    var point = new System.Drawing.Point((int)p.XValue, (int)p.YValue); 
    gr.Graphics.DrawLine(pen, point, pts[j);
}

Answer 3

您可以制作并引用此扩展程序，

namespace DrawingExtensions
{
    using System.Windows.Forms.DataVisualization.Charting;
    using System.Drawing;

    public static class Forms
    {
        public PointF ToPointF(this DataPoint source)
        {
            return new PointF(
                Convert.ToSingle(source.XValue),
                Convert.ToSingle(source.YValue));
        }

        public Point ToPoint(this DataPoint source)
        {
            return new Point(
                Convert.ToInt32(source.XValue),
                Convert.ToInt32(source.YValue));
        }
    }
}

你明显会使用这个，

var point = dataPoint.ToPoint();
var pointF = dataPoint.ToPointF();

或者，对于整个阵列，

var points = dataPoints.Select(p => p.ToPoint()).ToArray();
var pointFs = dataPoints.Select(p => p.ToPointF()).ToArray();

将DataPoint转换为Point

3 个答案: