如何更改图表系列颜色

我有一个系列，用数据库中的记录填充我的图表。 显示了7条记录，但是采用了sanme颜色。

我试图改变每个酒吧颜色而没有成功

下面是我试过的线，但我给了我一个大绿条（：

private void button1_Click(object sender, EventArgs e) { /*First empty the chart2 to fire the current data*/ if (cbChart.SelectedItem == null) { chart.Visible = false; chart.Controls.Clear(); } else //pnchart.Controls.Clear(); chart.Visible = true; chart.Titles.Clear(); /*Add a new title*/ Title bezeichung = new Title("Finance" + Environment.NewLine + "(GWU)", Docking.Top, new Font("Yu Gothic", 8, FontStyle.Bold), Color.Black); chart.Titles.Add(bezeichung); chart.Titles.Add(bezeichung2); if (cbChart.SelectedItem != null) { string S = ConfigurationManager.ConnectionStrings[""].ConnectionString; SqlConnection con = new SqlConnection(S); SqlCommand cmd = new SqlCommand(); cmd.Connection = con; cmd.CommandType = CommandType.StoredProcedure; cmd.CommandText = ("[dbo].[storedprocedure]"); cmd.Parameters.AddWithValue("@Table_Name", cbChart.SelectedValue.ToString()); SqlDataReader myReader; // DataReader to just read Data from the Datbase try { //DO SOMETHING con.Open(); myReader = cmd.ExecuteReader(); while (myReader.Read()) { //Parameters (Seriesname, x-axis data & y-axis data) this.chart.Series["Series"].Points.AddXY(myReader["Finance"], myReader["GWU"]); // remove grid lines chart.ChartAreas[0].AxisX.MajorGrid.LineWidth = 0; chart.ChartAreas[0].AxisY.MajorGrid.LineWidth = 0; chart.ChartAreas[0].AxisX.LabelStyle.Angle = -45; chart.Series["series1"].Points[0].Color = Color.Green; chart.Series["series1"].Points[1].Color = Color.Red; chart.Series["series1"].Points[2].Color = Color.PowderBlue; chart.Series["series1"].Points[3].Color = Color.Peru; chart.Series["series1"].Points[4].Color = Color.Pink; chart.Series["series1"].Points[5].Color = Color.Purple; } } catch (Exception ex) { MessageBox.Show(ex.Message); } finally { con.Close(); } } else { MessageBox.Show("Bitte ", "Info", MessageBoxButtons.OK, MessageBoxIcon.Warning); } } 

这是我在运行它后收到的错误消息：索引位于有效范围之外，索引不能为负且必须低于列表的大小

按下按钮后的图表：

Answer 1

您试图在系列中添加点之前更改点的颜色。 将下面的块移出while循环，并在尝试按索引访问之前检查是否有足够的点存在，

  chart.Series["series1"].Points[0].Color = Color.Green; chart.Series["series1"].Points[1].Color = Color.Red; chart.Series["series1"].Points[2].Color = Color.PowderBlue; chart.Series["series1"].Points[3].Color = Color.Peru; chart.Series["series1"].Points[4].Color = Color.Pink; chart.Series["series1"].Points[5].Color = Color.Purple; 

以下是您需要在代码中进行的更改，

 while (myReader.Read()) { //Parameters (Seriesname, x-axis data & y-axis data) this.chart.Series["Series"].Points.AddXY(myReader["Finance"], myReader["GWU"]); } if(chart.ChartAreas.Count > 0) { chart.ChartAreas[0].AxisX.MajorGrid.LineWidth = 0; chart.ChartAreas[0].AxisY.MajorGrid.LineWidth = 0; chart.ChartAreas[0].AxisX.LabelStyle.Angle = -45; } if(chart.Series["series1"].Points.Count > 5) { chart.Series["series1"].Points[0].Color = Color.Green; chart.Series["series1"].Points[1].Color = Color.Red; chart.Series["series1"].Points[2].Color = Color.PowderBlue; chart.Series["series1"].Points[3].Color = Color.Peru; chart.Series["series1"].Points[4].Color = Color.Pink; chart.Series["series1"].Points[5].Color = Color.Purple; }