ASP.NET图表控件，可以在饼图上使用渐变吗？

Question

我正在使用ASP.NET图表控件原型图。我有以下代码来生成我的图表。我试图尽可能接近客户的品牌准则。品牌准则在饼图分段中使用渐变。使用自定义颜色时可以这样吗？

/// <summary> 
    /// Create an image of a chart from the given data 
    /// </summary> 
    /// <param name="data">Dictionary of data, labels as key and value as value.</param> 
    /// <returns>The bytes of an image</returns> 
    private Byte[] CreatePieChart(Dictionary<string,string> data) 
    { 
     //Set up the chart 
     var chart = new Chart 
     { 
      Width = 550, 
      Height = 400, 
      RenderType = RenderType.BinaryStreaming, 
      AntiAliasing = AntiAliasingStyles.All, 
      TextAntiAliasingQuality = TextAntiAliasingQuality.High 
     }; 

     //Add the title 
     chart.Titles.Add("Chart 1"); 
     chart.Titles[0].Font = new Font("Arial", 16f); 

     //Set up labels etc 
     chart.ChartAreas.Add(""); 
     chart.ChartAreas[0].AxisX.TitleFont = new Font("Arial", 12f); 
     chart.ChartAreas[0].AxisY.TitleFont = new Font("Arial", 12f); 
     chart.ChartAreas[0].AxisX.LabelStyle.Font = new Font("Arial", 10f); 
     chart.ChartAreas[0].AxisX.LabelStyle.Angle = -90; 
     chart.ChartAreas[0].BackColor = Color.White; 

     //Set up the series and specify Pie chart 
     chart.Series.Add(""); 
     chart.Series[0].ChartType = SeriesChartType.Pie; 
     chart.Series[0].SetCustomProperty("PieLabelStyle", "outside"); 
     chart.Series[0].IsValueShownAsLabel = true; 
     chart.Series[0].BackGradientStyle = GradientStyle.Center; 

     //MAke the chart 3D 
     chart.ChartAreas[0].Area3DStyle.Enable3D = true; 
     //chart.ChartAreas[0].Area3DStyle.Perspective = 75; 
     chart.ChartAreas[0].Area3DStyle.Inclination = 0; 

     //Loop over the data and add it to the series 
     foreach (var item in data) 
     { 
      chart.Series[0].Points.AddXY(item.Key, Convert.ToDouble(item.Value)); 
     } 

     //Add a legend 
     chart.Legends.Add(""); 
     chart.Legends[0].InsideChartArea = ""; 

     Color[] myPalette = new Color[6]{ 
      Color.FromArgb(255,101,187,226), 
      Color.FromArgb(255,253,214,91), 
      Color.FromArgb(255,38,190,151), 
      Color.FromArgb(255,253,183,101), 
      Color.FromArgb(255,218,143,183), 
      Color.FromArgb(255,242,242,242)}; 

     chart.Palette = ChartColorPalette.None; 
     chart.PaletteCustomColors = myPalette; 

     byte[] chartBytes; 

     //Write the chart image to a stream and get the bytes 
     using (var chartimage = new MemoryStream()) 
     { 
      chart.SaveImage(chartimage, ChartImageFormat.Png); 
      chartBytes = chartimage.GetBuffer(); 
     } 

     return chartBytes; 
    } 

Answer 1

使用ASP.NET制图可以在饼图上获得渐变。

这里的相关线路：

 Color[] myPalette = new Color[5]{ 
      Color.FromArgb(255,101,187,226), 
      Color.FromArgb(255,253,214,91), 
      Color.FromArgb(255,38,190,151), 
      Color.FromArgb(255,253,183,101), 
      Color.FromArgb(255,218,143,183)}; 

     chart.Palette = ChartColorPalette.None; 
     chart.PaletteCustomColors = myPalette; 

     //Loop over the data and add it to the series 
     int i = 0; 
     foreach (var item in data) 
     { 
      chart.Series[0].Points.AddXY(item.Key, Convert.ToDouble(item.Value)); 
      chart.Series[0].Points[i].BackGradientStyle = GradientStyle.Center; 
      chart.Series[0].Points[i].Color = myPalette[i]; 
      chart.Series[0].Points[i].BackSecondaryColor = LightenColor(myPalette[i]); 
      //chart.Series[0].Points[i].SetCustomProperty("Exploded","true"); 

      i++; 
     } 

原型代码。产生可通过的渐变。