public static MorphicResult <MorphicUnit, MorphicUnit> SetHighContrastModeIsOn(bool isOn)
{
// NOTE: we lock on s_modifyHighContrastLock here to ensure that our application doesn't modify the system's HIGHCONTRAST settings while we're reading, updating and rewriting them
lock (s_modifyHighContrastLock)
{
// set up a HIGHCONTRAST structure; we'll use this to get and then update the high contrast settings
var highContrastInfo = new ExtendedPInvoke.HIGHCONTRAST();
highContrastInfo.Init();
IntPtr pointerToHighContrastInfo = Marshal.AllocHGlobal((int)highContrastInfo.cbSize);
Marshal.StructureToPtr(highContrastInfo, pointerToHighContrastInfo, false);
try
{
// get the current high contrast settings (which we will update in a moment)
var spiSuccess = PInvoke.User32.SystemParametersInfo(PInvoke.User32.SystemParametersInfoAction.SPI_GETHIGHCONTRAST, highContrastInfo.cbSize, pointerToHighContrastInfo, PInvoke.User32.SystemParametersInfoFlags.None);
if (spiSuccess == false)
{
return(MorphicResult.ErrorResult());
}
highContrastInfo = Marshal.PtrToStructure <ExtendedPInvoke.HIGHCONTRAST>(pointerToHighContrastInfo);
// set/clear the "high contrast on" flag
if (isOn == true)
{
highContrastInfo.dwFlags |= ExtendedPInvoke.HighContrastFlags.HCF_HIGHCONTRASTON;
}
else
{
highContrastInfo.dwFlags &= ~ExtendedPInvoke.HighContrastFlags.HCF_HIGHCONTRASTON;
}
Marshal.StructureToPtr(highContrastInfo, pointerToHighContrastInfo, false);
// write the new settings
// NOTE: we are asking the system to broadcast the contrast change to all top-level windows, but we are not asking it to save the (system-wide) setting to the user's profile; if we want to offer that as an option in the future we can OR SPIF_UPDATEINIFILE in our flags here
spiSuccess = PInvoke.User32.SystemParametersInfo(PInvoke.User32.SystemParametersInfoAction.SPI_SETHIGHCONTRAST, highContrastInfo.cbSize, pointerToHighContrastInfo, PInvoke.User32.SystemParametersInfoFlags.SPIF_SENDWININICHANGE);
if (spiSuccess == false)
{
return(MorphicResult.ErrorResult());
}
return(MorphicResult.OkResult());
}
finally
{
Marshal.FreeHGlobal(pointerToHighContrastInfo);
}
}
}
private static MorphicResult <HighContrastInfo, MorphicUnit> GetHighContrastInfo()
{
var highContrastInfo = new ExtendedPInvoke.HIGHCONTRAST();
highContrastInfo.Init();
IntPtr pointerToHighContrastInfo = Marshal.AllocHGlobal((int)highContrastInfo.cbSize);
Marshal.StructureToPtr(highContrastInfo, pointerToHighContrastInfo, false);
try
{
var spiSuccess = PInvoke.User32.SystemParametersInfo(PInvoke.User32.SystemParametersInfoAction.SPI_GETHIGHCONTRAST, highContrastInfo.cbSize, pointerToHighContrastInfo, PInvoke.User32.SystemParametersInfoFlags.None);
if (spiSuccess == false)
{
return(MorphicResult.ErrorResult());
}
highContrastInfo = Marshal.PtrToStructure <ExtendedPInvoke.HIGHCONTRAST>(pointerToHighContrastInfo);
}
finally
{
Marshal.FreeHGlobal(pointerToHighContrastInfo);
}
var result = new HighContrastInfo()
{
FeatureIsOn = ((highContrastInfo.dwFlags & ExtendedPInvoke.HighContrastFlags.HCF_HIGHCONTRASTON) == ExtendedPInvoke.HighContrastFlags.HCF_HIGHCONTRASTON),
FeatureCanBeTurnedOnAndOff = ((highContrastInfo.dwFlags & ExtendedPInvoke.HighContrastFlags.HCF_AVAILABLE) == ExtendedPInvoke.HighContrastFlags.HCF_AVAILABLE),
HotKeyIsEnabled = ((highContrastInfo.dwFlags & ExtendedPInvoke.HighContrastFlags.HCF_HOTKEYACTIVE) == ExtendedPInvoke.HighContrastFlags.HCF_HOTKEYACTIVE),
HotKeyPresentsConfirmationDialog = ((highContrastInfo.dwFlags & ExtendedPInvoke.HighContrastFlags.HCF_CONFIRMHOTKEY) == ExtendedPInvoke.HighContrastFlags.HCF_CONFIRMHOTKEY),
HotKeyPlaysSound = ((highContrastInfo.dwFlags & ExtendedPInvoke.HighContrastFlags.HCF_HOTKEYSOUND) == ExtendedPInvoke.HighContrastFlags.HCF_HOTKEYSOUND),
//ShowsVisualIndicatorWhenOn = ((highContrastInfo.dwFlags & ExtendedPInvoke.HighContrastFlags.HCF_INDICATOR) == ExtendedPInvoke.HighContrastFlags.HCF_INDICATOR),
HotKeyCanBeEnabled = ((highContrastInfo.dwFlags & ExtendedPInvoke.HighContrastFlags.HCF_HOTKEYAVAILABLE) == ExtendedPInvoke.HighContrastFlags.HCF_HOTKEYAVAILABLE),
//
DefaultColorScheme = highContrastInfo.lpszDefaultScheme
};
return(MorphicResult.OkResult(result));
}
