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CreateRectRgn (gdi32)

C# Signature:

static extern IntPtr CreateRectRgn(int nLeftRect, int nTopRect, int nRightRect, int nBottomRect);

VB.NET Signature:

<DllImport("gdi32.dll")> _
Private Shared Function CreateRectRgn(ByVal nLeftRect As Integer, ByVal nTopRect As Integer, ByVal nRightRect As Integer, ByVal nBottomRect As Integer) As IntPtr
End Function

User-Defined Types:




Tips & Tricks:

Please add some!

Sample Code:

// Up Top

        static extern IntPtr GetDC(IntPtr hWnd);

        static extern bool FillRgn(IntPtr hdc, IntPtr hrgn, IntPtr hbr);

        static extern IntPtr CreateRectRgn(int nLeftRect, int nTopRect, int nRightRect,
            int nBottomRect);

        static extern IntPtr CreateSolidBrush(uint crColor);

        static extern bool DeleteObject(IntPtr hObject);

// Then whereever:

                // This paints the current form black
                IntPtr wDc = GetDC(this.Handle);
                int mx = Screen.PrimaryScreen.WorkingArea.Width;
                int my = Screen.PrimaryScreen.WorkingArea.Height;
                IntPtr brush = CreateSolidBrush(0x0); // black, of format : //0x00bbggrr
                FillRgn(wDc, CreateRectRgn(0,0,mx,my), brush);

Alternative Managed API:

No managed API. GraphicsPath can be used to create a similar functionality.

Do you know one? Please contribute it!


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