How to save the shapes that I draw on the panel as binary

Question

I have a mini drawing program. I want to create a save button that saves the panel details (shapes and everything that is drawn) as a binary file. I have done this:

 SaveFileDialog sfd = new SaveFileDialog();
 BinaryFormatter bf = new BinaryFormatter();
 var stream = new BinaryReader(File.Open(sfd.FileName,FileMode.Create));
 bf.Serialize(stream,object);

but it has an error that using the object is invalid in bf.Serialize. How should I do it?

Answer 1

You do not need to serialize the panel, the panel is not serializable. You can consider any of these options:

• , . , . .
• , . . , , Visio.

:

• : , , .

• : , , , Save Load, . , , hit-testing moving shape. xml .

, .

Paint , DrawToBitmap :

private void button1_Click(object sender, EventArgs e)
{
    using (var bm = new Bitmap(panel1.Width, panel1.Height))
    {
        panel1.DrawToBitmap(bm, new Rectangle(0, 0, bm.Width, bm.Height));
        bm.Save(@"d:\panel.bmp", System.Drawing.Imaging.ImageFormat.Bmp); 
    }
}
private void panel1_Paint(object sender, PaintEventArgs e)
{
    e.Graphics.FillRectangle(Brushes.Red, 0, 0, 100, 100);
    e.Graphics.FillRectangle(Brushes.Blue, 50, 50, 100, 100);
}

, LineShape RectangleShape, Shape. , :

[Serializable]
public abstract class Shape
{
    public abstract void Draw(Graphics g);
    public override string ToString() { return GetType().Name; }
}

[Serializable]
public class LineShape : Shape
{
    public LineShape(){ Color = Color.Blue; Width = 2; }
    public Point Point1 { get; set; }
    public Point Point2 { get; set; }
    public int Width { get; set; }
    public Color Color { get; set; }
    public override void Draw(Graphics g)
    {
        using (var pen = new Pen(Color, Width))
            g.DrawLine(pen, Point1, Point2);
    }
}

[Serializable]
public class RectangleShape : Shape
{
    public RectangleShape() { Color = Color.Red; }
    public Rectangle Rectangle { get; set; }
    public Color Color { get; set; }
    public override void Draw(Graphics g)
    {
        using (var brush = new SolidBrush(Color))
            g.FillRectangle(brush, Rectangle);
    }
}

ShapesList . :

[Serializable]
public class ShapesList : List<Shape>
{
    public void Save(string file)
    {
        using (Stream stream = File.Open(file, FileMode.Create))
        {
            BinaryFormatter bin = new BinaryFormatter();
            bin.Serialize(stream, this);
        }
    }
    public void Load(string file)
    {
        using (Stream stream = File.Open(file, FileMode.Open))
        {
            BinaryFormatter bin = new BinaryFormatter();
            var shapes = (ShapesList)bin.Deserialize(stream);
            this.Clear();
            this.AddRange(shapes);
        }
    }
    public void Draw(Graphics g)
    {
        this.ForEach(x => x.Draw(g));
    }
}

:

ShapesList Shapes;
private void Form3_Load(object sender, EventArgs e)
{
    Shapes = new ShapesList();
    Shapes.Add(new RectangleShape() { Rectangle = new Rectangle(0, 0, 100, 100), 
        Color = Color.Green });
    Shapes.Add(new RectangleShape() { Rectangle = new Rectangle(50, 50, 100, 100), 
        Color = Color.Blue });
    Shapes.Add(new LineShape() { Point1 = new Point(0, 0), Point2 = new Point(150, 150), 
        Color = Color.Red });
    this.panel1.Invalidate();
}

private void button1_Click(object sender, EventArgs e)
{
    Shapes.Save(@"d:\shapes.bin");
    Shapes.Clear();
    this.panel1.Invalidate();
    MessageBox.Show("Shapes saved successfully.");
    Shapes.Load(@"d:\shapes.bin");
    this.panel1.Invalidate();
    MessageBox.Show("Shapes loaded successfully.");
}
private void panel1_Paint(object sender, PaintEventArgs e)
{
    e.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
    Shapes.Draw(e.Graphics);
}