微软图表：透明度

我想要一个具有透明背景的图表，因此 PNG 似乎是一个不错的选择。但是当我设置透明背景时，轴标签的质量急剧下降。我该如何解决？请参阅以下代码。就目前情况而言，图表具有透明背景，正如我所希望的那样，但文本质量很差。如果我注释掉两个“Color.Transparent”设置，则文本质量很好，但背景不透明。

如何获得透明度和漂亮的文本？

public static void Main(string[] args)
{
  Chart c = new Chart();
  c.TextAntiAliasingQuality = TextAntiAliasingQuality.High;

  Series s = new Series("Series1");
  c.Series.Clear();
  c.Series.Add(s);
  s.ChartType = SeriesChartType.Line;

  s.Color = Color.Black;

  ChartArea chartArea = new ChartArea("ChartArea1");
  c.ChartAreas.Clear();
  c.ChartAreas.Add(chartArea);

  chartArea.BackColor = Color.FromArgb(255, 255, 255);
  chartArea.BackSecondaryColor = Color.FromArgb(220, 220, 220);
  chartArea.BackGradientStyle = GradientStyle.TopBottom;

  chartArea.AxisX.LineColor = Color.Gray;
  chartArea.AxisX.LineWidth = 2;
  chartArea.AxisX.LineDashStyle = ChartDashStyle.Solid;

  chartArea.AxisY.LineColor = Color.Gray;
  chartArea.AxisY.LineWidth = 2;
  chartArea.AxisY.LineDashStyle = ChartDashStyle.Solid;

  chartArea.AxisX.MajorGrid.LineColor = Color.LightGray;
  chartArea.AxisX.MajorGrid.LineDashStyle = ChartDashStyle.Dash;

  chartArea.AxisY.MajorGrid.LineColor = Color.LightGray;
  chartArea.AxisY.MajorGrid.LineDashStyle = ChartDashStyle.Dash;

  c.BackColor = Color.Transparent;
  chartArea.BackColor = Color.Transparent;


  double[] x = new double[] { 1999, 2005 };
  double[] y = new double[] { 3210, 13456 };

  Axis ay = chartArea.AxisY;
  ay.Maximum = 13456;
  ay.Minimum = 3210;

  Axis ax = chartArea.AxisX;
  ax.Maximum = 2005;
  ax.Minimum = 1999;

  for (int i = 0; i < x.Length; i++)
  {
    double xvalue = x[i];
    double yvalue = y[i];
    s.Points.AddXY(xvalue, yvalue);
   }

   // Save chart-image to disk:
   c.SaveImage("chartimage.png", ChartImageFormat.Png);
}

设置图表的抗锯齿 to 抗锯齿样式.图形禁用文本的抗锯齿功能。

取自这个线程 http://social.msdn.microsoft.com/Forums/en-US/MSWinWebChart/thread/64c7d890-c98b-4392-9ec9-1b4af3e24300.