/// <devdoc>
/// Loads a picture from the requested stream.
/// </devdoc>
private void LoadPicture(UnsafeNativeMethods.IStream stream)
{
if (stream == null)
{
throw new ArgumentNullException(nameof(stream));
}
try {
Guid g = typeof(UnsafeNativeMethods.IPicture).GUID;
UnsafeNativeMethods.IPicture picture = null;
new SecurityPermission(SecurityPermissionFlag.UnmanagedCode).Assert();
try {
picture = UnsafeNativeMethods.OleCreateIPictureIndirect(null, ref g, true);
UnsafeNativeMethods.IPersistStream ipictureAsIPersist = (UnsafeNativeMethods.IPersistStream)picture;
ipictureAsIPersist.Load(stream);
if (picture != null && picture.GetPictureType() == NativeMethods.Ole.PICTYPE_ICON)
{
IntPtr cursorHandle = picture.GetHandle();
Size picSize = GetIconSize(cursorHandle);
if (DpiHelper.IsScalingRequired)
{
picSize = DpiHelper.LogicalToDeviceUnits(picSize);
}
handle = SafeNativeMethods.CopyImageAsCursor(new HandleRef(this, cursorHandle), NativeMethods.IMAGE_CURSOR,
picSize.Width, picSize.Height, 0);
ownHandle = true;
}
else
{
throw new ArgumentException(string.Format(SR.InvalidPictureType,
"picture",
"Cursor"), "picture");
}
}
finally {
CodeAccessPermission.RevertAssert();
// destroy the picture...
if (picture != null)
{
Marshal.ReleaseComObject(picture);
}
}
}
catch (COMException e) {
Debug.Fail(e.ToString());
throw new ArgumentException(SR.InvalidPictureFormat, "stream", e);
}
}
public override object ConvertNativeToManaged(object nativeValue, Com2PropertyDescriptor pd)
{
if (nativeValue == null)
{
return(null);
}
Debug.Assert(nativeValue is UnsafeNativeMethods.IPicture, "nativevalue is not IPicture");
UnsafeNativeMethods.IPicture nativePicture = (UnsafeNativeMethods.IPicture)nativeValue;
IntPtr handle = nativePicture.GetHandle();
if (lastManaged != null && handle == lastNativeHandle)
{
return(lastManaged);
}
lastNativeHandle = handle;
//lastPalette = nativePicture.GetHPal();
if (handle != IntPtr.Zero)
{
switch (nativePicture.GetPictureType())
{
case NativeMethods.Ole.PICTYPE_ICON:
pictureType = typeof(Icon);
lastManaged = Icon.FromHandle(handle);
break;
case NativeMethods.Ole.PICTYPE_BITMAP:
pictureType = typeof(Bitmap);
lastManaged = Image.FromHbitmap(handle);
break;
default:
Debug.Fail("Unknown picture type");
break;
}
pictureRef = new WeakReference(nativePicture);
}
else
{
lastManaged = null;
pictureRef = null;
}
return(lastManaged);
}
public override object ConvertManagedToNative(object managedValue, Com2PropertyDescriptor pd, ref bool cancelSet)
{
// don't cancel the set
cancelSet = false;
if (lastManaged != null && lastManaged.Equals(managedValue) && pictureRef != null && pictureRef.IsAlive)
{
return(pictureRef.Target);
}
// we have to build an IPicture
lastManaged = managedValue;
if (managedValue != null)
{
Guid g = typeof(UnsafeNativeMethods.IPicture).GUID;
NativeMethods.PICTDESC pictdesc = null;
bool own = false;
if (lastManaged is Icon)
{
pictdesc = NativeMethods.PICTDESC.CreateIconPICTDESC(((Icon)lastManaged).Handle);
}
else if (lastManaged is Bitmap)
{
pictdesc = NativeMethods.PICTDESC.CreateBitmapPICTDESC(((Bitmap)lastManaged).GetHbitmap(), lastPalette);
own = true;
}
else
{
Debug.Fail("Unknown Image type: " + managedValue.GetType().Name);
}
UnsafeNativeMethods.IPicture pict = UnsafeNativeMethods.OleCreatePictureIndirect(pictdesc, ref g, own);
lastNativeHandle = pict.GetHandle();
pictureRef = new WeakReference(pict);
return(pict);
}
else
{
lastManaged = null;
lastNativeHandle = lastPalette = IntPtr.Zero;
pictureRef = null;
return(null);
}
}
