填充闭合区域

using  System.Runtime.InteropServices;
 
[DllImport( " gdi32.dll " )]
public   static   extern  IntPtr SelectObject(IntPtr hdc, IntPtr hgdiobj);
[DllImport( " gdi32.dll " )]
public   static   extern  IntPtr CreateSolidBrush( int  crColor);
[DllImport( " gdi32.dll " )]
public   static   extern   bool  ExtFloodFill(IntPtr hdc,  int  nXStart,  int  nYStart,
     int  crColor,  uint  fuFillType);
[DllImport( " gdi32.dll " )]
public   static   extern   bool  DeleteObject(IntPtr hObject);
[DllImport( " gdi32.dll " )]
public   static   extern   int  GetPixel(IntPtr hdc,  int  x,  int  y);
public   static   uint  FLOODFILLBORDER  =   0 ;
public   static   uint  FLOODFILLSURFACE  =   1 ;
 
private   void  button1_Click( object  sender, EventArgs e)
{
    Graphics vGraphics  =  Graphics.FromHwnd(Handle);
    vGraphics.DrawRectangle(Pens.Blue,  new  Rectangle( 0 ,  0 ,  300 ,  300 ));
    vGraphics.DrawRectangle(Pens.Blue,  new  Rectangle( 50 ,  70 ,  300 ,  300 ));
    IntPtr vDC  =  vGraphics.GetHdc();
    IntPtr vBrush  =  CreateSolidBrush(ColorTranslator.ToWin32(Color.Red));
    IntPtr vPreviouseBrush  =  SelectObject(vDC, vBrush);
    ExtFloodFill(vDC,  10 ,  10 , GetPixel(vDC,  10 ,  10 ), FLOODFILLSURFACE);
    SelectObject(vDC, vPreviouseBrush);
    DeleteObject(vBrush);
    vGraphics.ReleaseHdc(vDC);
}

本文来自CSDN博客，转载请标明出处： http://blog.csdn.net/zswang/archive/2007/05/22/1621529.aspx