C#用自定义或指定颜色填充矩形

时间：2024-02-24 16:05:39

用到某处要使用自定义颜色填充图像，貌似Graphics.FillRectangle方法只能用Brush来填充。但是常规Brush都是Brushes定义好的Brush，怎么办呢？

GOOGLE了下有两种方法：
一、用新SolidBrush填充

 

public void FillByColor(Rectangle rect,Color c,Graphics G)
{
    G.FillRectangle(new SolidBrush(c), rect);
}


参考文章：《如何：创建线性渐变》


二、用API实现指定颜色填充一个闭合区域(未测试)
用API实现指定颜色填充 
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);
}

 

参考文章：http://www.csharpwin.com/csharpspace/9115r3566.shtml

 

 

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