如何获取显示模态对话框的监视器的DPI

Question

我有以下代码来检查显示表单的屏幕的DPI。它对于常规（无模式）窗口可以正常工作，但是如果对话框以模态显示，则返回显示主窗口的屏幕的DPI。明显的错误是通过调用Process.GetCurrentProcess（）。MainWindowHandle引起的，它似乎返回了主窗口的进程ID（因为模态窗口可能在调用窗口的进程下运行）。不幸的是，当必须在模式对话框中检测到DPI时，这会导致布局问题；当将DPI从一个监视器拖到另一个监视器时，会重新排列元素。

如何获取显示模式对话框的窗口的DPI？

谢谢！

-Pete

通话格式：

Dim factor As Single = GetDpiWindowMonitor(Me) / 96.0

被调用的代码：

'Get DPI of monitor containing this window by GetDpiForMonitor.
Public Function GetDpiWindowMonitor(ByVal curForm As Form) As Single
    'Get handle to this window.

    Process.GetCurrentProcess().Refresh()

    Dim handleWindow As Integer = Process.GetCurrentProcess().MainWindowHandle
    ' ^^^ This seems to return the handle of the main window, not the dialog

    'Get handle to monitor.
    Dim handleMonitor As Integer = W32.MonitorFromWindow(handleWindow, W32.MONITOR_DEFAULTTONEAREST)

    'Get DPI.
    Dim curDPI As Integer = GetDpiSpecifiedMonitor(curForm, handleMonitor)
    Return curDPI
End Function



'Get DPI of a specified monitor by GetDpiForMonitor.
Public Function GetDpiSpecifiedMonitor(ByVal curForm As Form,
                                       ByVal handleMonitor As Integer) As Single


    'Check if GetDpiForMonitor function is available.
    If Not IsEightOneOrNewer() Then
        If curForm.CurrentAutoScaleDimensions.Width = 0 Then
            If FrmRegisteredTo.CurrentAutoScaleDimensions.Width > 0 Then
                Return FrmRegisteredTo.CurrentAutoScaleDimensions.Width
            Else
                Return 96
            End If
        Else
            Return curForm.CurrentAutoScaleDimensions.Width
        End If

    End If

    'Get DPI.
    Dim dpiX As UInteger
    Dim dpiY As UInteger

    Dim result As Integer = W32.GetDpiForMonitor(handleMonitor, W32.Monitor_DPI_Type.MDT_Default, dpiX, dpiY)

    If (result <> 0) Then   'If not S_OK (= 0)
        Throw New Exception("Failed to get DPI of monitor containing this window.")
    End If

    Return Convert.ToSingle(dpiX)
End Function