public void ParkingWindow_SystemAware()
{
// run tests only on Windows 10 versions that support thread dpi awareness.
if (!PlatformDetection.IsWindows10Version1803OrGreater)
{
return;
}
// set thread awareness context to PermonitorV2(PMv2).
// if process/thread is not in PMv2, calling 'EnterDpiAwarenessScope' is a no-op and that is by design.
// In this case, we will be setting thread to PMv2 mode and then scope to UNAWARE
IntPtr originalAwarenessContext = User32.SetThreadDpiAwarenessContext(User32.DPI_AWARENESS_CONTEXT.PER_MONITOR_AWARE_V2);
try
{
using (DpiHelper.EnterDpiAwarenessScope(User32.DPI_AWARENESS_CONTEXT.SYSTEM_AWARE))
{
using var control = new Control();
ThreadContext ctx = GetContextForHandle(new HandleRef(this, control.Handle));
Assert.NotNull(ctx);
ParkingWindow parkingWindow = ctx.GetParkingWindowForContext(User32.DPI_AWARENESS_CONTEXT.SYSTEM_AWARE);
Assert.NotNull(parkingWindow);
IntPtr dpiContext = User32.GetWindowDpiAwarenessContext(parkingWindow.Handle);
Assert.True(User32.AreDpiAwarenessContextsEqual(User32.DPI_AWARENESS_CONTEXT.SYSTEM_AWARE, dpiContext));
}
}
finally
{
// reset back to original awareness context.
User32.SetThreadDpiAwarenessContext(originalAwarenessContext);
}
}
/// <summary>
/// Gets the DPI awareness.
/// </summary>
/// <returns>The thread's/process' current HighDpi mode</returns>
internal static HighDpiMode GetWinformsApplicationDpiAwareness()
{
// For Windows 10 RS2 and above
if (OsVersion.IsWindows10_1607OrGreater)
{
IntPtr dpiAwareness = User32.GetThreadDpiAwarenessContext();
if (User32.AreDpiAwarenessContextsEqual(dpiAwareness, User32.DPI_AWARENESS_CONTEXT.SYSTEM_AWARE))
{
return(HighDpiMode.SystemAware);
}
if (User32.AreDpiAwarenessContextsEqual(dpiAwareness, User32.DPI_AWARENESS_CONTEXT.UNAWARE))
{
return(HighDpiMode.DpiUnaware);
}
if (User32.AreDpiAwarenessContextsEqual(dpiAwareness, User32.DPI_AWARENESS_CONTEXT.PER_MONITOR_AWARE_V2))
{
return(HighDpiMode.PerMonitorV2);
}
if (User32.AreDpiAwarenessContextsEqual(dpiAwareness, User32.DPI_AWARENESS_CONTEXT.PER_MONITOR_AWARE))
{
return(HighDpiMode.PerMonitor);
}
if (User32.AreDpiAwarenessContextsEqual(dpiAwareness, User32.DPI_AWARENESS_CONTEXT.UNAWARE_GDISCALED))
{
return(HighDpiMode.DpiUnawareGdiScaled);
}
}
else if (OsVersion.IsWindows8_1OrGreater)
{
SHCore.GetProcessDpiAwareness(IntPtr.Zero, out SHCore.PROCESS_DPI_AWARENESS processDpiAwareness);
switch (processDpiAwareness)
{
case SHCore.PROCESS_DPI_AWARENESS.UNAWARE:
return(HighDpiMode.DpiUnaware);
case SHCore.PROCESS_DPI_AWARENESS.SYSTEM_AWARE:
return(HighDpiMode.SystemAware);
case SHCore.PROCESS_DPI_AWARENESS.PER_MONITOR_AWARE:
return(HighDpiMode.PerMonitor);
}
}
else
{
// Available on Vista and higher
return(User32.IsProcessDPIAware().IsTrue() ? HighDpiMode.SystemAware : HighDpiMode.DpiUnaware);
}
// We should never get here, except someone ported this with force to < Windows 7.
return(HighDpiMode.DpiUnaware);
}
/// <summary>
/// Tries to compare two DPIawareness context values. Return true if they were equal.
/// Return false when they are not equal or underlying OS does not support this API.
/// </summary>
/// <returns>true/false</returns>
public static bool TryFindDpiAwarenessContextsEqual(DpiAwarenessContext?dpiContextA, DpiAwarenessContext?dpiContextB)
{
if (dpiContextA == null)
{
return(dpiContextB == null); // true if both null but not either
}
else if (dpiContextB == null)
{
return(false); // because we know A is not null
}
if (AreDpiAwarenessContextsEqualIsAvailable())
{
return(User32.AreDpiAwarenessContextsEqual((DpiAwarenessContext)dpiContextA, (DpiAwarenessContext)dpiContextB));
}
// legacy OS that does not have this API available.
return(false);
}
