public string GetCurrentDpiConfiguration()
{
StringBuilder stringBuilder = new StringBuilder();
var awareness = PerMonitorDPIHelper.GetPerMonitorDPIAware();
var systemDpi = PerMonitorDPIHelper.GetSystemDPI();
switch (awareness)
{
case PROCESS_DPI_AWARENESS.PROCESS_DPI_UNAWARE:
stringBuilder.AppendFormat("Application is DPI Unaware. Using {0} DPI.", systemDpi);
break;
case PROCESS_DPI_AWARENESS.PROCESS_SYSTEM_DPI_AWARE:
stringBuilder.AppendFormat("Application is System DPI Aware. Using System DPI: {0}.", systemDpi);
break;
case PROCESS_DPI_AWARENESS.PROCESS_PER_MONITOR_DPI_AWARE:
stringBuilder.AppendFormat("Application is Per-Monitor DPI Aware. Using \tmonitor DPI = {0} \t(System DPI = {1}).", m_currentDPI, systemDpi);
break;
}
return(stringBuilder.ToString());
}
public PerMonitorDPIWindow()
{
Loaded += OnLoaded;
if (PerMonitorDPIHelper.SetPerMonitorDPIAware())
{
m_perMonitorEnabled = true;
}
else
{
throw new Exception("Enabling Per-monitor DPI Failed. Do you have [assembly: DisableDpiAwareness] in your assembly manifest [AssemblyInfo.cs]?");
}
}
protected void OnLoaded(Object sender, RoutedEventArgs args)
{
// WPF has already scaled window size, graphics and text based on system DPI. In order to scale the window based on monitor DPI, update the
// window size, graphics and text based on monitor DPI. For example consider an application with size 600 x 400 in device independent pixels
// - Size in device independent pixels = 600 x 400
// - Size calculated by WPF based on system/WPF DPI = 192 (scale factor = 2)
// - Expected size based on monitor DPI = 144 (scale factor = 1.5)
// Similarly the graphics and text are updated updated by applying appropriate scale transform to the top level node of the WPF application
// Important Note: This method overwrites the size of the window and the scale transform of the root node of the WPF Window. Hence,
// this sample may not work "as is" if
// - The size of the window impacts other portions of the application like this WPF Window being hosted inside another application.
// - The WPF application that is extending this class is setting some other transform on the root visual; the sample may
// overwrite some other transform that is being applied by the WPF application itself.
if (m_perMonitorEnabled)
{
m_source = (HwndSource)PresentationSource.FromVisual(this);
m_source.AddHook(this.HandleMessages);
//Calculate the DPI used by WPF; this is same as the system DPI.
m_wpfDPI = 96.0 * m_source.CompositionTarget.TransformToDevice.M11;
//Get the Current DPI of the monitor of the window.
m_currentDPI = PerMonitorDPIHelper.GetDpiForWindow(m_source.Handle);
//Calculate the scale factor used to modify window size, graphics and text
m_scaleFactor = m_currentDPI / m_wpfDPI;
//Update Width and Height based on the on the current DPI of the monitor
Width = Width * m_scaleFactor;
Height = Height * m_scaleFactor;
//Update graphics and text based on the current DPI of the monitor
UpdateLayoutTransform(m_scaleFactor);
}
}
