Question

我有一个Chart Control，我试图用sqldatasource中的一些系列动态填充，这是我的图表控件：

<asp:Chart ID="chartMonthly" runat="server" Width="920px" ImageLocation="~/Images/Temp/ChartPic_#SEQ(300,3)" Palette="Berry">
        <ChartAreas>
            <asp:ChartArea Name="line"></asp:ChartArea>
        </ChartAreas>
    </asp:Chart>

以下是我动态添加系列和点数的方法：

Private Sub chartMonthly_DataBinding(sender As Object, e As System.EventArgs) Handles chartMonthly.DataBinding

    Dim conStr As String = ConfigurationManager.ConnectionStrings("GenshenPOS").ConnectionString
    Dim conn As New SqlConnection(conStr)

    conn.Open()

    Dim sqlPoints As New SqlCommand("SELECT [m] AS [月], [Store] AS [門市], SUM([amount]) AS [NTD] FROM vwMonthly WHERE [y] = " & dropYear.SelectedValue & " GROUP BY [m], [Store]", conn)

    Dim reader As SqlDataReader = sqlPoints.ExecuteReader()

    While reader.Read()

        If chartMonthly.Series.IndexOf(reader.Item("門市")) = -1 Then

            chartMonthly.Series.Add(reader.Item("門市"))
            chartMonthly.Legends.Add(reader.Item("門市"))
            chartMonthly.Series(reader.Item("門市")).ChartType = SeriesChartType.Line
            chartMonthly.Series(reader.Item("門市")).ChartArea = "line"

        End If

        chartMonthly.Series(reader.Item("門市")).Points.AddXY("月", "NTD")

    End While

    conn.Close()

End Sub

图表正在正确读取商店的名称并根据它们创建系列，但我的图表没有数据 - 没有轴有值，系列的行在图表的底部作为0 /空值。

我已单独运行基础查询，数据就在那里，我假设它看到了数据，否则系列和图例就不会被创建，所以我想我错过了一些东西，我添加点到系列？！

Image of chart control with series but displaying no datapoints

Answer 1

您可以尝试通过显式转换为datetime（月初）来添加Points.AddXY

chartMonthly.Series(reader.Item("門市")).Points.AddXY(New DateTime(Integer.Parse(dropYear.SelectedValue), Integer.Parse(reader("月").ToString()), 1), "NTD")

图表控件中的绑定点

1 个答案: