WPF에서 DPI를 어떻게 얻을 수 있습니까?

WPF에서 DPI를 어떻게 얻을 수 있습니까?

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WPF에서 DPI를 어떻게 얻을 수 있습니까?

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http://blogs.msdn.com/jaimer/archive/2007/03/07/getting-system-dpi-in-wpf-app.aspx 가 작동하는 것 같습니다.

PresentationSource source = PresentationSource.FromVisual(this);

double dpiX, dpiY;
if (source != null) {
    dpiX = 96.0 * source.CompositionTarget.TransformToDevice.M11;
    dpiY = 96.0 * source.CompositionTarget.TransformToDevice.M22;
}

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var dpiXProperty = typeof(SystemParameters).GetProperty("DpiX", BindingFlags.NonPublic | BindingFlags.Static);
var dpiYProperty = typeof(SystemParameters).GetProperty("Dpi", BindingFlags.NonPublic | BindingFlags.Static);

var dpiX = (int)dpiXProperty.GetValue(null, null);
var dpiY = (int)dpiYProperty.GetValue(null, null);

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.NET 4.6.2 Preview 이상을 사용하면 VisualTreeHelper.GetDpi(Visual visual). DpiScale주어진 항목 Visual이 렌더링되거나 렌더링 된 DPI를 알려주 는 구조를 반환합니다 .

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"실제"모니터 dpi를 얻는 유일한 방법은 다음과 같습니다. 언급 된 다른 모든 기술은 대부분의 모니터에 맞지 않는 96을 말합니다.

 public class ScreenInformations
{
    public static uint RawDpi { get; private set; }

    static ScreenInformations()
    {
        uint dpiX;
        uint dpiY;
        GetDpi(DpiType.RAW, out dpiX, out dpiY);
        RawDpi = dpiX;
    }

    /// <summary>
    /// Returns the scaling of the given screen.
    /// </summary>
    /// <param name="dpiType">The type of dpi that should be given back..</param>
    /// <param name="dpiX">Gives the horizontal scaling back (in dpi).</param>
    /// <param name="dpiY">Gives the vertical scaling back (in dpi).</param>
    private static void GetDpi(DpiType dpiType, out uint dpiX, out uint dpiY)
    {
        var point = new System.Drawing.Point(1, 1);
        var hmonitor = MonitorFromPoint(point, _MONITOR_DEFAULTTONEAREST);

        switch (GetDpiForMonitor(hmonitor, dpiType, out dpiX, out dpiY).ToInt32())
        {
            case _S_OK: return;
            case _E_INVALIDARG:
                throw new ArgumentException("Unknown error. See https://msdn.microsoft.com/en-us/library/windows/desktop/dn280510.aspx for more information.");
            default:
                throw new COMException("Unknown error. See https://msdn.microsoft.com/en-us/library/windows/desktop/dn280510.aspx for more information.");
        }
    }

    //https://msdn.microsoft.com/en-us/library/windows/desktop/dd145062.aspx
    [DllImport("User32.dll")]
    private static extern IntPtr MonitorFromPoint([In]System.Drawing.Point pt, [In]uint dwFlags);

    //https://msdn.microsoft.com/en-us/library/windows/desktop/dn280510.aspx
    [DllImport("Shcore.dll")]
    private static extern IntPtr GetDpiForMonitor([In]IntPtr hmonitor, [In]DpiType dpiType, [Out]out uint dpiX, [Out]out uint dpiY);

    const int _S_OK = 0;
    const int _MONITOR_DEFAULTTONEAREST = 2;
    const int _E_INVALIDARG = -2147024809;
}

/// <summary>
/// Represents the different types of scaling.
/// </summary>
/// <seealso cref="https://msdn.microsoft.com/en-us/library/windows/desktop/dn280511.aspx"/>
public enum DpiType
{
    EFFECTIVE = 0,
    ANGULAR = 1,
    RAW = 2,
}

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2015 년부터 내 대답을 업데이트했습니다. 다음은 Windows 10의 최신 DPI 기능 (특히 창 / 응용 프로그램 / 프로세스 등의 DPI_AWARENESS를 지원하는 유일한 방법 인 GetDpiForWindow 기능) 을 사용하는 유틸리티 코드입니다 . 이전 버전 (모니터 당 dpi 및 데스크톱 dpi)이므로 Windows 7에서 계속 작동합니다.

WPF 나 Winforms에 의존하지 않고 Windows 자체에만 의존합니다.

// note this class considers dpix = dpiy
public static class DpiUtilities
{
    // you should always use this one and it will fallback if necessary
    // https://docs.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-getdpiforwindow
    public static int GetDpiForWindow(IntPtr hwnd)
    {
        var h = LoadLibrary("user32.dll");
        var ptr = GetProcAddress(h, "GetDpiForWindow"); // Windows 10 1607
        if (ptr == IntPtr.Zero)
            return GetDpiForNearestMonitor(hwnd);

        return Marshal.GetDelegateForFunctionPointer<GetDpiForWindowFn>(ptr)(hwnd);
    }

    public static int GetDpiForNearestMonitor(IntPtr hwnd) => GetDpiForMonitor(GetNearestMonitorFromWindow(hwnd));
    public static int GetDpiForNearestMonitor(int x, int y) => GetDpiForMonitor(GetNearestMonitorFromPoint(x, y));
    public static int GetDpiForMonitor(IntPtr monitor, MonitorDpiType type = MonitorDpiType.Effective)
    {
        var h = LoadLibrary("shcore.dll");
        var ptr = GetProcAddress(h, "GetDpiForMonitor"); // Windows 8.1
        if (ptr == IntPtr.Zero)
            return GetDpiForDesktop();

        int hr = Marshal.GetDelegateForFunctionPointer<GetDpiForMonitorFn>(ptr)(monitor, type, out int x, out int y);
        if (hr < 0)
            return GetDpiForDesktop();

        return x;
    }

    public static int GetDpiForDesktop()
    {
        int hr = D2D1CreateFactory(D2D1_FACTORY_TYPE.D2D1_FACTORY_TYPE_SINGLE_THREADED, typeof(ID2D1Factory).GUID, IntPtr.Zero, out ID2D1Factory factory);
        if (hr < 0)
            return 96; // we really hit the ground, don't know what to do next!

        factory.GetDesktopDpi(out float x, out float y); // Windows 7
        Marshal.ReleaseComObject(factory);
        return (int)x;
    }

    public static IntPtr GetDesktopMonitor() => GetNearestMonitorFromWindow(GetDesktopWindow());
    public static IntPtr GetShellMonitor() => GetNearestMonitorFromWindow(GetShellWindow());
    public static IntPtr GetNearestMonitorFromWindow(IntPtr hwnd) => MonitorFromWindow(hwnd, MONITOR_DEFAULTTONEAREST);
    public static IntPtr GetNearestMonitorFromPoint(int x, int y) => MonitorFromPoint(new POINT { x = x, y = y }, MONITOR_DEFAULTTONEAREST);

    private delegate int GetDpiForWindowFn(IntPtr hwnd);
    private delegate int GetDpiForMonitorFn(IntPtr hmonitor, MonitorDpiType dpiType, out int dpiX, out int dpiY);

    private const int MONITOR_DEFAULTTONEAREST = 2;

    [DllImport("kernel32", CharSet = CharSet.Auto, SetLastError = true)]
    private static extern IntPtr LoadLibrary(string lpLibFileName);

    [DllImport("kernel32", CharSet = CharSet.Ansi, SetLastError = true)]
    private static extern IntPtr GetProcAddress(IntPtr hModule, string lpProcName);

    [DllImport("user32")]
    private static extern IntPtr MonitorFromPoint(POINT pt, int flags);

    [DllImport("user32")]
    private static extern IntPtr MonitorFromWindow(IntPtr hwnd, int flags);

    [DllImport("user32")]
    private static extern IntPtr GetDesktopWindow();

    [DllImport("user32")]
    private static extern IntPtr GetShellWindow();

    [StructLayout(LayoutKind.Sequential)]
    private partial struct POINT
    {
        public int x;
        public int y;
    }

    [DllImport("d2d1")]
    private static extern int D2D1CreateFactory(D2D1_FACTORY_TYPE factoryType, [MarshalAs(UnmanagedType.LPStruct)] Guid riid, IntPtr pFactoryOptions, out ID2D1Factory ppIFactory);

    private enum D2D1_FACTORY_TYPE
    {
        D2D1_FACTORY_TYPE_SINGLE_THREADED = 0,
        D2D1_FACTORY_TYPE_MULTI_THREADED = 1,
    }

    [InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("06152247-6f50-465a-9245-118bfd3b6007")]
    private interface ID2D1Factory
    {
        int ReloadSystemMetrics();

        [PreserveSig]
        void GetDesktopDpi(out float dpiX, out float dpiY);

        // the rest is not implemented as we don't need it
    }
}

public enum MonitorDpiType
{
    Effective = 0,
    Angular = 1,
    Raw = 2,
}

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이것이 내가 WPF에서 "스케일 팩터"를 얻는 방법입니다. 내 노트북의 해상도는 1920x1440입니다.

int resHeight = System.Windows.Forms.Screen.PrimaryScreen.Bounds.Height;  // 1440
int actualHeight = SystemParameters.PrimaryScreenHeight;  // 960
double ratio = actualHeight / resHeight;
double dpi = resHeigh / actualHeight;  // 1.5 which is true because my settings says my scale is 150%

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사용 GetDeviceCaps기능 :

    static void Main(string[] args)
    {
        // 1.25 = 125%
        var dpi = GetDpi() ;
    }

    [DllImport("user32.dll")]
    public static extern int ReleaseDC(IntPtr hWnd, IntPtr hDC);

    [DllImport("user32.dll")]
    public static extern IntPtr GetDC(IntPtr hwnd);

    [DllImport("gdi32.dll")]
    static extern int GetDeviceCaps(IntPtr hdc, int nIndex);

    private static float GetDpi()
    {
        IntPtr desktopWnd = IntPtr.Zero;
        IntPtr dc = GetDC(desktopWnd);
        var dpi = 100f;
        const int LOGPIXELSX = 88;
        try
        {
            dpi = GetDeviceCaps( dc, LOGPIXELSX);
        }
        finally
        {
            ReleaseDC(desktopWnd, dc);
        }
        return dpi / 96f;
    }

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https://blogs.windows.com/buildingapps/2017/01/25/calling-windows-10-apis-desktop-application/#FJtMAIFjbtXiLQAp.97 이 있습니다.

2017 년 1 월 25 일 3:54 오후

"데스크톱 응용 프로그램에서 Windows 10 API 호출"및

https://docs.microsoft.com/en-us/uwp/api/windows.devices.display.displaymonitor

"Display​Monitor Class"

Namespace: Windows.Devices.Display Assemblies:Windows.Devices.Display.dll, Windows.dll

Provides information about a display monitor device connected to the system.

These data include commonly used information from the monitor's Extended Display Identification Data (EDID, which is an industry-standard display descriptor block that nearly all monitors use to provide descriptions of supported modes and general device information) and DisplayID (which is a newer industry standard that provides a superset of EDID).

Raw​DpiX
Gets the physical horizontal DPI of the monitor (based on the monitor’s native resolution and physical size).

Raw​DpiY
Gets the physical vertical DPI of the monitor (based on the monitor’s native resolution and physical size).

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Basic monitor info in Windows from 2006

https://docs.microsoft.com/en-us/windows/desktop/wmicoreprov/msmonitorclass

MSMonitorClass class

WmiMonitorRawEEdidV1Block class

WmiMonitorBasicDisplayParams class

MaxHorizontalImageSize ( EDID byte 21 )

MaxVerticalImageSize ( EDID byte 22 )

( Sizes in EDID are in centimeters above and in millimeters in EDID Detailed Timing Descriptor

12 Horizontal image size, mm, 8 lsbits (0–4095 mm, 161 in)
13 Vertical image size, mm, 8 lsbits (0–4095 mm, 161 in)
14 Bits 7–4 Horizontal image size, mm, 4 msbits
Bits 3–0 Vertical image size, mm, 4 msbits

)

and

https://social.msdn.microsoft.com/Forums/vstudio/en-US/e7bb9384-b343-4543-ac0f-c98b88a7196f/wpf-wmi-just-get-an-empty-string

참고URL : https://stackoverflow.com/questions/1918877/how-can-i-get-the-dpi-in-wpf