//其实，我不用这三个 属性 好多年了

 //而且，这三个属性 在关键时刻还有可能 帮倒忙

 //关键是：这三个属性，鸟用都没有 —— 不能消除锯齿

 g.SmoothingMode = SmoothingMode.HighQuality;

 g.InterpolationMode = InterpolationMode.HighQualityBicubic;

 g.CompositingQuality = CompositingQuality.HighQuality;

             Bitmap bitmap0 = new Bitmap(, );

             using (Graphics g = Graphics.FromImage(bitmap0))

             {

                 g.Clear(Color.Transparent); //以透明色 作为背景

                 g.DrawString("科技救国  (透明色背景)", new Font("微软雅黑", ), new SolidBrush(Color.Black), new PointF(, ));

                 bitmap0.Save(@"D:\XXX\TestString0.png", ImageFormat.Png);

             }

             Bitmap bitmap1 = new Bitmap(, );

             using (Graphics g = Graphics.FromImage(bitmap1))

             {

                 g.Clear(Color.White);

                 g.DrawString("科技救国  (白色背景)", new Font("微软雅黑", ), new SolidBrush(Color.Black), new PointF(, ));

                 bitmap1.Save(@"D:\XXX\TestString1.png", ImageFormat.Png);

             }

             Bitmap bitmap2 = new Bitmap(bitmap1.Width, bitmap1.Height);

             for (int x = ; x < bitmap1.Width; x++)

                 for (int y = ; y < bitmap1.Height; y++)

                 {

                     //这段代码还有很大的优化空间

                     Color color = bitmap1.GetPixel(x, y);

                     byte a = (byte)(((short)( - color.R) + (short)( - color.G) + (short)( - color.B)) / );

                     Color color2 = Color.FromArgb(a, , , );

                     bitmap2.SetPixel(x, y, color2);

                 }

             bitmap2.Save(@"D:\XXX\TestString2.png", ImageFormat.Png);