我如何用點填充矩形的邊緣？

Question

我用鼠標繪製了一個矩形，現在我想要在繪製矩形時繪製矩形，它將在每個矩形邊的底部，頂部，底部，右側繪製點。

這是怎麼看，當我剛剛繪製矩形，如：

，我想，雖然我畫實時矩形添加/墊的每個邊緣帶有X個點的矩形。例如，在每個邊緣上10個綠點與它們之間具有精確的空間。

例如我加入油漆點只是爲了說明我的意思：

就在綠點應該是在厚的矩形的紅線和紅線。 綠點應填寫。 點之間應該有精確的空間。

我只是在頂部畫了一些點，但它應該在左下角和右側。

這是我現在如何繪製正方形矩形的矩形。

在Form1的頂部：

private Bitmap _bmpBU = null; 
public static Rectangle mRect; 

在構造函數中：

this.DoubleBuffered = true; 
_bmpBU = new Bitmap(@"D:\MyWeatherStation-Images-And-Icons\radar090.PNG"); 

pictureBox1鼠標移動事件：

private void pictureBox1_MouseMove(object sender, MouseEventArgs e) 
     { 
      if (e.Button == MouseButtons.Left) 
      { 
       mRect = new Rectangle(mRect.Left, mRect.Top, e.X - mRect.Left, e.Y - mRect.Top); 
       pictureBox1.Invalidate(); 
      } 
     } 

pictureBox1鼠標按下事件：

private void pictureBox1_MouseDown(object sender, MouseEventArgs e) 
     { 
      mRect = new Rectangle(e.X, e.Y, 0, 0); 
      Image iOLd = this.pictureBox1.Image; 
      Bitmap bmp = (Bitmap)_bmpBU.Clone(); 

      this.pictureBox1.Image = bmp; 
      if (iOLd != null) 
       iOLd.Dispose(); 
      pictureBox1.Invalidate(); 
     } 

而且pictureBox1漆事件：

private void pictureBox1_Paint(object sender, PaintEventArgs e) 
     { 
      using (Pen pen = new Pen(Color.Red, 2)) 
      { 
       e.Graphics.DrawRectangle(pen, mRect); 
      } 
     } 

我需要以某種方式在油漆事件，而它的繪製矩形也會墊，並添加綠點，每個邊緣。

Answer 1

private Point RectStartPoint; 
private Image img; 
private Image imgClone; 
private Pen myPen; 
private n = 10; //number of points 

你必須初始化這些對象，也許在：

public Form1() 
    { 
     InitializeComponent(); 

     myPen = new Pen(Brushes.Red, 2); 
     //Bitmap to hold the picturebox image 
     img = new Bitmap(pictureBox1.Width, pictureBox1.Height); 
     Graphics g; 
     using (g = Graphics.FromImage(img)) 
     { 
      g.DrawImage(imageOfPicturebox, 0, 0, pictureBox1.Width, pictureBox1.Height); 
     } 

     //image to hold the original picturebox. We need it to clear img to the original 
     //picturebox image 
     imgClone = (Bitmap)img.Clone(); 

     //We draw always on img and then we invalidate 
     pictureBox1.Image = img; 
    } 

private void pictureBox1_MouseDown(object sender, MouseEventArgs e) 
    { 
     RectStartPoint = e.Location; 
    } 

    private void pictureBox1_MouseMove(object sender, MouseEventArgs e) 
    { 
     if (e.Button == MouseButtons.Left && e.Location != RectStartPoint) 
     { 
      DrawRectangle(e.Location); 
     } 
    } 

    private void DrawRectangle(Point pnt) 
    { 
     Graphics g = Graphics.FromImage(img); 
     int width, height, i, x, y; 

     g.SmoothingMode = SmoothingMode.AntiAlias; 

     //Clear img from the rectangle we drawn previously 
     g.DrawImage(imgClone, 0, 0); 


     if (pnt.X == RectStartPoint.X || pnt.Y == RectStartPoint.Y) 
     { 
      g.DrawLine(myPen, RectStartPoint.X, RectStartPoint.Y, pnt.X, pnt.Y); 
     } 
     else 
     { 
      g.DrawRectangle(myPen, Math.Min(RectStartPoint.X, pnt.X), Math.Min(RectStartPoint.Y, pnt.Y), 
          Math.Abs(RectStartPoint.X - pnt.X), Math.Abs(RectStartPoint.Y - pnt.Y)); 

      //width of spaces between points 
      width = (int)((Math.Abs(RectStartPoint.X - pnt.X))/(n - 1)); 
      //height of spaces between points 
      height = (int)((Math.Abs(RectStartPoint.Y - pnt.Y))/(n - 1)); 
      //we always want the upper left x, y coordinates as a reference drawing clockwise 
      x = Math.Min(RectStartPoint.X, pnt.X); 
      y = Math.Min(RectStartPoint.Y, pnt.Y); 

      //Drawing the points. change the 3, 6 values for larger ones 
      for (i = 0; i < n - 1; i++) 
      { 
       //Up side 
       g.FillEllipse(Brushes.Green, new Rectangle(x - 3, Math.Min(RectStartPoint.Y, pnt.Y) - 3, 6, 6)); 
       //Right side 
       g.FillEllipse(Brushes.Green, new Rectangle(Math.Min(RectStartPoint.X, pnt.X) + Math.Abs(RectStartPoint.X - pnt.X) - 3, y - 3, 6, 6)); 
       //Bottom side 
       g.FillEllipse(Brushes.Green, new Rectangle(x - 3, Math.Min(RectStartPoint.Y, pnt.Y) + Math.Abs(RectStartPoint.Y - pnt.Y) - 3, 6, 6)); 
       //Left side 
       g.FillEllipse(Brushes.Green, new Rectangle(Math.Min(RectStartPoint.X, pnt.X) - 3, y - 3, 6, 6)); 

       x += width; 
       y += height; 
      } 
      g.FillEllipse(Brushes.Green, new Rectangle(Math.Min(RectStartPoint.X, pnt.X) + Math.Abs(RectStartPoint.X - pnt.X) - 3, 
          Math.Min(RectStartPoint.Y, pnt.Y) - 3, 6, 6)); 
      g.FillEllipse(Brushes.Green, new Rectangle(Math.Min(RectStartPoint.X, pnt.X) + Math.Abs(RectStartPoint.X - pnt.X) - 3, 
         Math.Min(RectStartPoint.Y, pnt.Y) + Math.Abs(RectStartPoint.Y - pnt.Y) - 3, 6, 6)); 
     } 

     g.Dispose(); 

     //draw img to picturebox 
     pictureBox1.Invalidate(); 
    } 

Answer 2

這僅僅是數學。添加這一功能：

private void DrawPointsOnRectangle(Graphics g, int numberOfPoints) 
{ 
    var brush = new SolidBrush(Color.DarkGreen); 
    const int rectanglePenWidth = 2; 

    //North & South 
    int spacing = mRect.Width/(numberOfPoints - 1); 

    for (int x = 0; x < numberOfPoints; x++) 
    { 
     g.FillEllipse(brush, mRect.X + (x * spacing) - rectanglePenWidth - 5, mRect.Y - 7, 15, 15); 
     g.FillEllipse(brush, mRect.X + (x * spacing) - rectanglePenWidth - 5, mRect.Y - 7 + mRect.Height, 15, 15);  
    } 

    //East & West 
    spacing = mRect.Height/(numberOfPoints - 1); 

    for (int y = 0; y < numberOfPoints; y++) 
    { 
     g.FillEllipse(brush, mRect.X - rectanglePenWidth - 5, mRect.Y - 7 + (y * spacing), 15, 15); 
     g.FillEllipse(brush, mRect.X - rectanglePenWidth - 5 + mRect.Width, mRect.Y - 7 + (y * spacing), 15, 15); 
    } 
} 

並修改pictureBox1_Paint函數調用新的功能：

private void pictureBox1_Paint(object sender, PaintEventArgs e) 
{ 
    using (Pen pen = new Pen(Color.Red, 2)) 
    { 
     e.Graphics.DrawRectangle(pen, mRect); 
     DrawPointsOnRectangle(e.Graphics, 5); 
    } 
} 

應該這樣做！您可以將5參數更改爲您想要的每個點上的許多點。