c# - 使用变量访问图表

Question

我有一个 C# WinForms 应用程序，它有四个图表控件，用于以图形方式显示一些分析结果。

我有适用于每个图表的代码，但是为了提高效率和重用代码，我定义了一个代码块来:

• 创建所需的系列，
• 从数据库中提取数据并将结果分配给适当的系列
• 将系列添加到图表
• 自定义图表外观。

由于数据在设计时不存在，因此上述所有操作都是动态完成的。

我希望重用的工作代码是:

// Add both series to the chart.  
ChartName.Series.AddRange(new Series[] { series1, series2 });  

// Cast the chart's diagram to the XYDiagram type, to access its axes.  
XYDiagram diagram = (XYDiagram)ChartName.Diagram; 

我想将 ChartName 对象更改为可以传递每个图表的变量，以便重新使用代码。类似的东西(注意这不起作用):-

var VChart = this.Controls.Find(ChartName, true);  

// Add both series to the chart.  
VChart.Series.AddRange(new Series[] { series1, series2 });  

// Cast the chart's diagram to the XYDiagram type, to access its axes.  
XYDiagram diagram = (XYDiagram)VChart.Diagram; 

任何关于如何将变量传递到 ChartName 的想法、提示、技巧等都将不胜感激。

完整代码:

    void Generate_Chart()
    {
        // Create two stacked bar series.
        Series series1 = new Series("Data", ViewType.Bar);
        Series series2 = new Series("Ben", ViewType.Line);

        try
        {                    
            using (var cmd = new SQLiteCommand(m_dbConnection))
            for (int i = LoopMin; i < LoopMax; i++)
            {
                // Retrieve the actual calculated values from the database
                cmd.CommandText = "SELECT " + Chart_SourceActualValue + " FROM " + Chart_SourceTable + " WHERE Value = " + i + "";
                Chart_SeriesA_Value = Convert.ToInt32(cmd.ExecuteScalar());

                // Retrieve the expected values from the database
                cmd.CommandText = "SELECT " + Chart_BenExpValue + " FROM " + Chart_SourceTable + " WHERE Value = " + i + "";
                Chart_SeriesB_Value = Convert.ToInt32(cmd.ExecuteScalar());

                // Add the dynamically created values to a series point for the chart
                series1.Points.Add(new SeriesPoint(i, Chart_SeriesA_Value));
                series2.Points.Add(new SeriesPoint(i, Chart_SeriesB_Value));
            }
        }
        catch (Exception)
        {                
            throw;
        }

        // Add both series to the chart.
        //this.Controls.Find(varChart, true)
        ChartName.Series.AddRange(new Series[] { series1, series2 });

        // Remove the GridLines from the chart for better UI
        // Cast the chart's diagram to the XYDiagram type, to access its axes.
        XYDiagram diagram = (XYDiagram)ChartName.Diagram;
        // Customize the appearance of the axes' grid lines.
        diagram.AxisX.GridLines.Visible = false;
        }        
}

Answer 1

这听起来像是您要用一个变量替换硬编码的 ChartName，这样您就可以调用您的例程四次不同的时间，每次都使用不同的图表。我已经采用了您的代码并替换了图表控件和设置的一些全局变量，并将它们作为您传递给函数的参数:

void Generate_Chart(DevExpress.XtraCharts.ChartControl chartCtrl,
                   string chart_sourceActualValue,
                    string chart_sourceTable,
                   string chart_benExpValue
                   )
    {
        // Create two stacked bar series.
        Series series1 = new Series("Data", ViewType.Bar);
        Series series2 = new Series("Ben", ViewType.Line);

        try
        {                    
            using (var cmd = new SQLiteCommand(m_dbConnection))
            for (int i = LoopMin; i < LoopMax; i++)
            {
                // Retrieve the actual calculated values from the database
                cmd.CommandText = "SELECT " + sourceActualValue + " FROM " + 
                     chart_sourceTable + " WHERE Value = " + i + "";
                Chart_SeriesA_Value = Convert.ToInt32(cmd.ExecuteScalar());

                // Retrieve the expected values from the database
                cmd.CommandText = "SELECT " + chart_benExpValue + " FROM " + 
                         chart_sourceTable + " WHERE Value = " + i + "";
                Chart_SeriesB_Value = Convert.ToInt32(cmd.ExecuteScalar());

                // Add the dynamically created values 
                // to a series point for the chart
                series1.Points.Add(new SeriesPoint(i, Chart_SeriesA_Value));
                series2.Points.Add(new SeriesPoint(i, Chart_SeriesB_Value));
            }
        }
        catch (Exception)
        {                
            throw;
        }

        // Add both series to the chart.
        chartCtrl.Series.AddRange(new Series[] { series1, series2 });

        // Remove the GridLines from the chart for better UI
        // Cast the chart's diagram to the XYDiagram type, to access its axes.
        XYDiagram diagram = (XYDiagram)chartCtrl.Diagram;
        // Customize the appearance of the axes' grid lines.
        diagram.AxisX.GridLines.Visible = false;
        }        
}

然后，您最终使用原始值作为参数调用此方法:

void Generate_Chart(ChartName, Chart_SourceActualValue, Chart_SourceTable, 
                    Chart_BenExpValue);

// call it three other times passing in the different specifics for that chart. e.g.
void Generate_Chart(SomeOtherChartName, SomeOtherChart_SourceActualValue, 
                    SomeOhterChart_SourceTable, SomeOtherChart_BenExpValue);

.....