c# - 我怎样才能得到我所有显示器的比例因子？

Question

Microsoft 不知道如何帮助我，所以我不得不在这里问。

我有三个显示器...

• 屏幕 1:3840 x 2160，缩放比例 150%
• 屏幕 2:1920 x 1200，缩放 100%
• 屏幕 3:1920 x 1200，缩放 100%

我需要在 VB.net 或 C# 中获取每个显示器的缩放比例。

Microsoft 建议我使用此代码:

Private Declare Function GetDeviceCaps Lib "gdi32.dll" (hdc As IntPtr, nIndex As Integer) As Integer

Public Enum DeviceCap
    VERTRES = 10
    DESKTOPVERTRES = 117
End Enum

Private Sub MainWindow_Loaded(sender As Object, e As RoutedEventArgs) Handles Me.Loaded
    For Each screen As Forms.Screen In Forms.Screen.AllScreens
        Dim pnt = New System.Drawing.Point(screen.Bounds.Left + 1, screen.Bounds.Top + 1)
        Dim mon = MonitorFromPoint(pnt, 2)
        Dim fac As Single = GetScalingFactor(mon)
        Console.WriteLine($"Factor: {fac}")
    Next
End Sub

Private Function GetScalingFactor(monitorHandle As IntPtr) As Single
    Dim g As Graphics = Graphics.FromHwnd(IntPtr.Zero)
    Dim desktop As IntPtr = g.GetHdc()
    Dim LogicalScreenHeight As Integer = GetDeviceCaps(desktop, CInt(DeviceCap.VERTRES))
    Dim PhysicalScreenHeight As Integer = GetDeviceCaps(desktop, CInt(DeviceCap.DESKTOPVERTRES))
    Dim ScreenScalingFactor As Single = CSng(PhysicalScreenHeight) / CSng(LogicalScreenHeight)
    Return ScreenScalingFactor
End Function

但它会为我的所有屏幕返回 1 的比例。

我需要它独立于我的应用程序是否是 dpiAware，所以我必须以某种方式从屏幕控制面板读取它。

该解决方案必须适用于 Windows 10 和 Windows Server 2012 R2 远程桌面客户端。

Answer 1

我相信你可以使用 ResolutionScale DisplayInformation 中的属性(property)类(class)。这会为您检索一个带有比例因子的枚举，但我不知道它是否独立于 dpiAware。