Csharp/C Sharp/2D Graphics/Screen

Get Screen Resolution

  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ruponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;
  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
    }
    static void Main() 
    {
      Application.Run(new Form1());
    }
    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      Bitmap bmp = new Bitmap("winter.jpg");
      g.DrawImage(bmp, 0, 0);
      Console.WriteLine("Screen resolution: " + g.DpiX + "DPI");
      Console.WriteLine("Image resolution: " + bmp.HorizontalResolution + "DPI");
      Console.WriteLine("Image Width: " + bmp.Width);
      Console.WriteLine("Image Height: " + bmp.Height);
      SizeF s = new SizeF(bmp.Width * (g.DpiX / bmp.HorizontalResolution),
                bmp.Height * (g.DpiY / bmp.VerticalResolution));
      Console.WriteLine("Display size of image: " + s);
    }
    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

Perform a Screen Capture

 

using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Windows.Forms;
public class DesktopCapture {
    [DllImport("user32.dll")]
    private extern static IntPtr GetDesktopWindow();
    [DllImport("user32.dll")]
    private extern static IntPtr GetDC(IntPtr windowHandle);
    [DllImport("gdi32.dll")]
    private extern static IntPtr GetCurrentObject(IntPtr hdc,
      ushort objectType);
    [DllImport("user32.dll")]
    private extern static void ReleaseDC( IntPtr hdc );
    const int OBJ_BITMAP = 7;
    public static Bitmap Capture() {
        IntPtr desktopWindow = GetDesktopWindow();
        IntPtr desktopDC = GetDC( desktopWindow );
        IntPtr desktopBitmap = GetCurrentObject(desktopDC, OBJ_BITMAP);
        Bitmap desktopImage = Image.FromHbitmap( desktopBitmap );
        ReleaseDC(desktopDC);
        return desktopImage;
    }
}