使用 C# 进行 FloodFill

Question

我正在尝试使用 C# 重写一些旧的 vb6 代码。问题是，当我在 vb 中使用 FloodFill 时，它会在 FloodFill 的影响下保存图像。使用 C# 则不然。这是 VB6 的代码段：

hTempBrush = CreateSolidBrush(&H400000)   
'Select the brush into the dc.
hPrevBrush = SelectObject(Maparea.hdc, hTempBrush)
'Fill the area.
FloodFill Maparea.hdc, (100 ), (200), MapColor
SelectObject Maparea.hdc, hPrevBrush
DeleteObject hTempBrush
SavePicture Maparea.Picture, "filename.bmp" ' saves picture with flood fill affect

这是c#

Graphics g2 = Graphics.FromHwnd(pictureBox1.handle);
IntPtr vDC = g2.GetHdc();
IntPtr vBrush = CreateSolidBrush(ColorTranslator.ToWin32(Color.Navy));
IntPtr vPreviouseBrush = SelectObject(vDC, vBrush);
int hh = ColorTranslator.ToWin32(Color.Wheat);
FloodFill(vDC, 100, 200, hh);
SelectObject(vDC, vPreviouseBrush);
DeleteObject(vBrush);
pictureBox1.Image.Save("map.bmp");  // saves without the affect of floodfill
g2.ReleaseHdc(vDC);

如有任何帮助，我们将不胜感激。

Answer 1

我找到了答案。我必须使用 BitBlt，以便保存控制界面上出现的所有内容。

private void button4_Click(object sender, EventArgs e)
{
    var bmp = new Bitmap(pictureBox1.Width, pictureBox1.Height);
    using (var bmpGraphics = Graphics.FromImage(bmp))
    {
        var despDC = bmpGraphics.GetHdc();
        using (Graphics formGraphics = Graphics.FromHwnd(pictureBox1.Handle))
        {
            var srcDC = formGraphics.GetHdc();
            BitBlt(despDC, 0, 0, pictureBox1.Width, pictureBox1.Height, srcDC, 0, 0, SRCCOPY);
            formGraphics.ReleaseHdc(srcDC);
        }
        bmpGraphics.ReleaseHdc(despDC);
    }
    bmp.Save("map1.jpg");