private static void FillRectanglesImpl(Graphics g, Color color, Rectangle[] rects)
{
uint nativeColor = (uint)(color.R + (color.G << 8) + (color.B << 16));
IntPtr hdc = IntPtr.Zero;
IntPtr brush = IntPtr.Zero;
IntPtr oldObject = IntPtr.Zero;
try
{
hdc = g.GetHdc();
brush = SafeNativeMethods.CreateSolidBrush(nativeColor);
if (brush == IntPtr.Zero)
{
NativeMethods.ThrowOnWin32Error("CreateSolidBrush returned NULL");
}
oldObject = SafeNativeMethods.SelectObject(hdc, brush);
foreach (Rectangle rect in rects)
{
NativeStructs.RECT nativeRect;
nativeRect.left = rect.Left;
nativeRect.top = rect.Top;
nativeRect.right = rect.Right;
nativeRect.bottom = rect.Bottom;
int result = SafeNativeMethods.FillRect(hdc, ref nativeRect, brush);
if (result == 0)
{
NativeMethods.ThrowOnWin32Error("FillRect returned zero");
}
}
}
finally
{
if (oldObject != IntPtr.Zero)
{
SafeNativeMethods.SelectObject(hdc, oldObject);
oldObject = IntPtr.Zero;
}
if (brush != IntPtr.Zero)
{
SafeNativeMethods.DeleteObject(brush);
brush = IntPtr.Zero;
}
if (hdc != IntPtr.Zero)
{
g.ReleaseHdc(hdc);
hdc = IntPtr.Zero;
}
}
GC.KeepAlive(g);
}
