I had two problems with the accepted answer.
Screen
class are incorrect when display scaling is used and your application is not declared dpiAware.Here's my updated solution using the Screen.AllScreens
static property and calling EnumDisplaySettings
using p/invoke to get the real screen resolution.
using System.Drawing;
using System.Linq;
using System.Runtime.InteropServices;
using System.Windows.Forms;
class Program
{
const int ENUM_CURRENT_SETTINGS = -1;
static void Main()
{
foreach (Screen screen in Screen.AllScreens)
{
DEVMODE dm = new DEVMODE();
dm.dmSize = (short)Marshal.SizeOf(typeof(DEVMODE));
EnumDisplaySettings(screen.DeviceName, ENUM_CURRENT_SETTINGS, ref dm);
using (Bitmap bmp = new Bitmap(dm.dmPelsWidth, dm.dmPelsHeight))
using (Graphics g = Graphics.FromImage(bmp))
{
g.CopyFromScreen(dm.dmPositionX, dm.dmPositionY, 0, 0, bmp.Size);
bmp.Save(screen.DeviceName.Split('\\').Last() + ".png");
}
}
}
[DllImport("user32.dll")]
public static extern bool EnumDisplaySettings(string lpszDeviceName, int iModeNum, ref DEVMODE lpDevMode);
[StructLayout(LayoutKind.Sequential)]
public struct DEVMODE
{
private const int CCHDEVICENAME = 0x20;
private const int CCHFORMNAME = 0x20;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 0x20)]
public string dmDeviceName;
public short dmSpecVersion;
public short dmDriverVersion;
public short dmSize;
public short dmDriverExtra;
public int dmFields;
public int dmPositionX;
public int dmPositionY;
public ScreenOrientation dmDisplayOrientation;
public int dmDisplayFixedOutput;
public short dmColor;
public short dmDuplex;
public short dmYResolution;
public short dmTTOption;
public short dmCollate;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 0x20)]
public string dmFormName;
public short dmLogPixels;
public int dmBitsPerPel;
public int dmPelsWidth;
public int dmPelsHeight;
public int dmDisplayFlags;
public int dmDisplayFrequency;
public int dmICMMethod;
public int dmICMIntent;
public int dmMediaType;
public int dmDitherType;
public int dmReserved1;
public int dmReserved2;
public int dmPanningWidth;
public int dmPanningHeight;
}
}
References:
https://stackoverflow.com/a/36864741/987968 http://pinvoke.net/default.aspx/user32/EnumDisplaySettings.html?diff=y