C# Signature:
[DllImport("gdi32.dll")]
static extern bool RoundRect(IntPtr hdc, int nLeftRect, int nTopRect,
int nRightRect, int nBottomRect, int nWidth, int nHeight);
User-Defined Types:
None.
Notes:
None.
Tips & Tricks:
Please add some!
Sample Code:
public class GDI32
{
#region GDI32 Functions
[DllImport("gdi32.dll")]
public static extern bool RoundRect(RECT lpRect, Point point);
[DllImport("gdi32.dll")]
public static extern bool RoundRect(IntPtr hdc, int nLeftRect, int nTopRect,
int nRightRect, int nBottomRect, int nWidth, int nHeight);
[DllImport("gdi32.dll")]
public static extern IntPtr CreateSolidBrush(uint crColor);
[DllImport("gdi32.dll")]
public static extern IntPtr CreatePen(int fnPenStyle, int nWidth, uint crColor);
[DllImport("gdi32.dll")]
public static extern IntPtr SelectObject(IntPtr hdc, IntPtr hgdiobj);
[DllImport("gdi32.dll")]
public static extern bool DeleteObject(IntPtr hObject);
public static int RGB(Color color)
{
/*
byte [] RGBCOLORS = new byte [4];
RGBCOLORS[0] = color.R;
RGBCOLORS[1] = color.G;
RGBCOLORS[2] = color.B;
RGBCOLORS[3] = 0;
return BitConverter.ToInt32(RGBCOLORS, 0);
*/
return color.ToArgb() & 0xffffff;
}
#endregion
}
public class RoundControl : System.Windows.Forms.Control
{
protected override void OnPaint(PaintEventArgs e)
{
DrawRoundRect(e.Graphics)
}
public void DrawRoundRect(Graphics gr)
{
RECT rect = new RECT(0, 0, this.Width, this.Height);
IntPtr hDC = gr.GetHdc();
IntPtr thePen = GDI32.CreatePen(0, 1, (uint)GDI32.RGB(Color.White));
IntPtr theBrush = GDI32.CreateSolidBrush((uint)GDI32.RGB(Color.White));
IntPtr oldPen = GDI32.SelectObject(hDC, thePen);
IntPtr oldBrush = GDI32.SelectObject(hDC, theBrush);
GDI32.RoundRect(hDC, 0, 0, this.Width, this.Height, 20, 20);
GDI32.SelectObject(hDC, oldPen);
GDI32.DeleteObject(thePen);
GDI32.SelectObject(hDC, oldBrush);
GDI32.DeleteObject(theBrush);
gr.ReleaseHdc(hDC);
}
}
Alternative Managed API:
Do you know one? Please contribute it!
