Question

我有一个C＃程序，需要显示一个包含2个serie对象的图表。目前我只有一个包含2个数据表的数据集。这两个表具有相同的布局。我将数据集绑定到图表的datasource属性并执行databind（）方法。它只显示一个系列。

我认为解决方案在于定义自定义bindingcontext，但我似乎无法弄明白。有人能帮帮我吗？感谢。

以下是我的一些代码：

        DataSet dataSet = new DataSet();

        DataTable dataTable = database.Query("select sum(amount) as monthamount, month(transdate) as month from transaction where year(transdate)=" + balanceDateTimePicker.Value.Year + " group by month");
        dataSet.Tables.Add(dataTable);

        dataTable = database.Query("select sum(amount) as monthamount, month(transdate) as month from transaction where year(transdate)=" + balanceDateTimePicker.Value.AddYears(-1).Year + " group by month");
        dataSet.Tables.Add(dataTable);

        reoccuranceChart.DataSource = dataSet;
        System.Windows.Forms.DataVisualization.Charting.Series series = reoccuranceChart.Series["Series1"];
        series.XValueMember = "month";
        series.YValueMembers = "monthamount";
        series.ChartType = System.Windows.Forms.DataVisualization.Charting.SeriesChartType.Column;
        series.IsVisibleInLegend = false;

        series = reoccuranceChart.Series["Series2"];
        series.XValueMember = "month";
        series.YValueMembers = "monthamount";
        series.ChartType = System.Windows.Forms.DataVisualization.Charting.SeriesChartType.Column;
        series.IsVisibleInLegend = false;

        reoccuranceChart.DataBind();

Answer 1

我找到了。它实际上相当简单。我所要做的就是单独绑定系列点：

        DataSet dataSet = new DataSet();

        DataTable dataTable = database.Query("select sum(amount) as monthamount, month(transdate) as month from transaction where year(transdate)=" + balanceDateTimePicker.Value.Year + " group by month");
        dataSet.Tables.Add(dataTable);

        dataTable = database.Query("select sum(amount) as monthamount, month(transdate) as month from transaction where year(transdate)=" + balanceDateTimePicker.Value.AddYears(-1).Year + " group by month");
        dataSet.Tables.Add(dataTable);

        System.Windows.Forms.DataVisualization.Charting.Series series = reoccuranceChart.Series["Now"];
        series.ChartType = System.Windows.Forms.DataVisualization.Charting.SeriesChartType.Column;
        //series.IsVisibleInLegend = false;
        series.Points.DataBind(dataSet.Tables[0].DefaultView, "month", "monthamount", "");

        series = reoccuranceChart.Series["Last year"];
        series.ChartType = System.Windows.Forms.DataVisualization.Charting.SeriesChartType.Column;
        //series.IsVisibleInLegend = false;
        series.Points.DataBind(dataSet.Tables[1].DefaultView, "month", "monthamount", "");

Answer 2

我认为您的问题在于重用dataTable变量。您需要为第二个查询创建第二个DataTable以防止重新分配第一个查询，因为Add函数不会复制表中的数据，它只保存对它的引用。尝试更改：

dataTable = database.Query ...

到

 DataTable dataTable2 = database.Query...

然后将其添加为第二个表，看看是否修复了它。

如何定义数据源的布局？

2 个答案: