Question

我已经在一个绘制网格点的程序上工作了几天，由于方法不好/复杂，我不得不重新开始几次。我现在已经到了一个点，我必须从表单上的点击点（点）到第二个点击点（点）绘制一条线。说真的，我花了几个小时的时间来寻找合适的方法。至于现在，我只是设法从表格上的一个点到随机点击表格上的另一个点... 有人可以帮助完成代码，它只是让我感到沮丧的是我在绘制网格点的所有尝试之后没有任何进展。所以我想做的是“从点击的点（点）到表格上的第二个点击点（点）画一条线。”

见下面的代码：

Form1.cs中：

public partial class Form1 : Form
{
    private GridDrawing drawing;

    private Point point1;
    private Point point2;
    List<Point> p1List = new List<Point>(); //Temp
    List<Point> p2List = new List<Point>(); //Temp

    //True if point1 must be updated
    //False if point2 must be updated
    private bool firstPoint = true;

    private int sizeOfDot;
    private int rows;
    private int columns;

    public Form1()
    {
        InitializeComponent();
        sizeOfDot = 10;     //The size of the dot
        rows = 6;           //The amount of rows for the matrix
        columns = 8;        //The amount of columns for the matrix
    }

    private void Form_Paint(object sender, PaintEventArgs e)
    {
        e.Graphics.FillRectangle(Brushes.White, ClientRectangle);   //Fill the form in white
        drawing = new GridDrawing(this, rows, columns);             //Control, Rows, Columns

        foreach (var piece in drawing.Pieces)                           //Draws all the dots
        {
            e.Graphics.FillEllipse(Brushes.Black, (piece.Dot.X - sizeOfDot / 2),
                (piece.Dot.Y - sizeOfDot / 2), sizeOfDot, sizeOfDot);   //Draws the dot
        }

        using (var pen = new Pen(Color.Black, 2))
        {
            for (int i = 0; i < p1List.Count; i++)
            {
                e.Graphics.DrawLine(pen, p1List[i], p2List[i]);
            }
        }
    }

    private void startToolStripMenuItem_Click(object sender, EventArgs e)
    {}

    private void Form1_MouseDown(object sender, MouseEventArgs e)
    {
        if (firstPoint)             //Update point1 or point2
        {
            //Point 1
            point1.X = e.X;
            point1.Y = e.Y;
        }
        else
        {
            //Point 2
            point2.X = e.X;
            point2.Y = e.Y;

            p1List.Add(point1);
            p2List.Add(point2);
        }
        firstPoint = !firstPoint;   //Change the bool value
        Invalidate();               //Redraw
    }

    private void Form1_SizeChanged(object sender, EventArgs e)
    {
        Invalidate();
    }
}

GridDrawing.cs：

public class GridDrawing
{
    private int columns;
    private int rows;
    private List<GridPiece> pieces;
    private Point dot;

    //private Point point1; //point1 to start drawing line from
    //private Point point2; //point2 to end drawing line from

    /// <summary>
    /// Constructs a grid
    /// </summary>
    /// <param name="ctrl"></param>
    /// <param name="rows"></param>
    /// <param name="columns"></param>
    /// <param name="sizeOfDot"></param>
    public GridDrawing(Control ctrl, int rows, int columns)
    {
        this.rows = rows;               // The amount of rows in the matrix.
        this.columns = columns;         // The amount of columns in the matrix.

        this.pieces = new List<GridPiece>();                // Initializes the List GridPieces

        int xOffset = (int)ctrl.ClientRectangle.Width / (columns + 1);  // FP offset for X
        int yOffset = (int)ctrl.ClientRectangle.Height / (rows + 1);    // FP offset for Y

        //Generate the dots
        for (int i = 0; i < rows; i++)          //Matrix with 6 rows                      
        {
            for (int j = 0; j < columns; j++)   //Matrix with 8 columns
            {
                dot = new Point((j + 1) * xOffset, (i + 1) * yOffset);  // Center of the dot
                GridPiece p = new GridPiece(dot);  // Creates a piece
                pieces.Add(p);                     // Puts the piece that has to be drawn in the List<GridPiece>pieces
            }
        }
    }

    public List<GridPiece> Pieces   //Property List<GridPiece>pieces
    {
        get { return this.pieces; }
    }

    public Point Dot                //Property Point dot
    {
        get { return this.dot; }
    }
}

GridPiece.cs：

public class GridPiece
{
    private Point dot;

    /// <summary>
    /// Constructor of GriedPiece
    /// </summary>
    /// <param name="bmpPic"></param>
    /// <param name="position"></param>
    public GridPiece(Point dot)
    {
        this.dot = dot;
    }

    public Point Dot
    {
        get { return dot; }
    }
}

这是一个例子，我试图让它看起来像 EXAMPLE

有人可以帮助我吗？

Answer 1

以下是如何执行此操作。添加以下代码

  public class Line
{
    public float X1 { get; set; }
    public float X2 { get; set; }
    public float Y1 { get; set; }
    public float Y2 { get; set; }
}


public sealed class Grid : Panel
{
    readonly DotDrawing drawing = new DotDrawing();
    private List<Line> Markers { get; set; }

    public Grid()
    {
        this.DoubleBuffered = true;
        Markers = new List<Line>();
    }
    protected override void OnPaint(PaintEventArgs e)
    {

        foreach (Line line in Markers)
        {
            using (Pen pen = new Pen(Brushes.Black))
            {
                pen.Width = 2;
                e.Graphics.SmoothingMode = SmoothingMode.HighQuality;
                e.Graphics.DrawLine(pen, line.X1, line.Y1, line.X2, line.Y2);
            }
        }drawing.Render(e.Graphics);
        base.OnPaint(e);
    }

    private Dot lastDot;
    protected override void OnMouseDown(MouseEventArgs e)
    {
        base.OnMouseDown(e);
        var x = this.drawing.GetDotFromPoint(e.Location);
        if (x != null)
        {
            lastDot = x;

        }
        else
        {
            lastDot = null;
        }
    }
    protected override void OnMouseUp(MouseEventArgs e)
    {
        base.OnMouseUp(e);
        var x = this.drawing.GetDotFromPoint(e.Location);
        if (x != null)
        {
            Line line = new Line();
            line.X1 = lastDot.Center.X;
            line.Y1 = lastDot.Center.Y;

            line.X2 = x.Center.X;
            line.Y2 = x.Center.Y;
            this.Markers.Add(line);
            Invalidate();
        }
    }

}
public class Dot
{
    public PointF Location { get; set; }
    public int Radius { get; set; }
    public PointF Center
    {
        get
        {
            return new PointF(this.Bounds.Left + (float)this.Radius,
                this.Bounds.Top + (float)this.Radius);
        }
    }
    public RectangleF Bounds
    {
        get
        {
            return new RectangleF(Location, new SizeF(2 * Radius, 2 * Radius));
        }
    }

    public Dot()
    {
        Radius = 5;
    }
}
public class DotDrawing
{
    private List<Dot> Dots { get; set; }
    public int RowCount { get; set; }
    public int ColumnCount { get; set; }
    public int ColumnSpacing { get; set; }
    public int RowSpacing { get; set; }
    public int DotRadius { get; set; }

    public DotDrawing()
    {
        Dots = new List<Dot>();
        DotRadius = 10;
        ColumnCount = 15;
        RowCount = 25;
        this.RowSpacing = 30;
        this.ColumnSpacing = 30;
    }
    public void Render(Graphics g)
    {
        this.Dots.Clear();
        float x = 0;
        float y = 0;
        for (int i = 0; i < RowCount; i++)
        {
            for (int j = 0; j < ColumnCount; j++)
            {
                {
                    Dot dot = new Dot();
                    dot.Location = new PointF(x, y);
                    using (SolidBrush brush = new SolidBrush(ColorTranslator.FromHtml("#009aff")))
                    {
                        g.FillEllipse(brush, dot.Location.X, dot.Location.Y, DotRadius, DotRadius);

                    }

                    x += (DotRadius + ColumnSpacing);
                    Dots.Add(dot);
                }
            }
            x = 0;
            y += (DotRadius + this.RowSpacing);
        }
    }

    public Dot GetDotFromPoint(PointF point)
    {
        for (int i = 0; i < this.Dots.Count; i++)
        {

            RectangleF rect = this.Dots[i].Bounds;
            rect.Inflate(new SizeF(3, 3));
            Region region = new Region(rect);
            if (region.IsVisible(point))
            {
                return this.Dots[i];
            }


        }
        return null;
    }

}

从工具框中拖动网格。鼠标单击任何点而不释放它指向另一个网格，您将看到效果。

在Form MouseDown上从点到点（点到点）绘制一条线

1 个答案: