C＃：如何在x轴线图中以DateTime类型绘制？

如何解决C＃：如何在x轴线图中以DateTime类型绘制？

我目前正在使用InteractiveDataDisplay.WPF在WPF中处理线图。我希望能够绘制带有DateTime类型的x轴和带有浮点类型的y轴。通过MYSQL数据库检索数据

如上图所示，由于我已将DateTime列表转换为double类型的OLE格式，因此折线图不可读。我没有将其输入为DateTime列表的原因是，每次尝试打开uniquewindow.cs时，我都会收到一个异常“从'datetime'到'double'列表的无效转换”。

这是代码：

C＃：

unique_window.xaml.cs

public unique_window(int id)
        {
            uniquebatches a = new uniquebatches(id);

            //assigning x and y axis for graphs with data from the batch
            var y1 = a.templist;
            var y2 = a.llist;
            var x = a.tlist;

            //drawing linegraph with the data
            linegrapht.Plot(x,y1);
            linegraphh.Plot(x,y2);
        }

uniquebatches.cs

public uniquebatches(int id)
{
            using (MySqlConnection connection = new MySqlConnection(CS))
            {
                string command = "SELECT * FROM table WHERE BatchID = " + id;
                MySqlDataAdapter adapter = new MySqlDataAdapter();
                adapter.SelectCommand = new MySqlCommand(command,connection);
                adapter.Fill(dt);
            }
            singleBatch = dt.DefaultView;
            
            //putting respective rows into generic lists in order to use for linegraph.
            templist = singleBatch.ToTable().Rows.OfType<DataRow>()
                .Select(dr => dr.Field<float>("Temp")).ToList();

            llist = singleBatch.ToTable().Rows.OfType<DataRow>()
               .Select(dr => dr.Field<float>("Hum")).ToList();

            List<DateTime> _tlist = singleBatch.ToTable().Rows.OfType<DataRow>()
                .Select(dr => dr.Field<DateTime>("date")).ToList();

            //converting DateTime generic list to a double list for OLE Automation date.
            List<double> __tlist = new List<double>();

            foreach (DateTime item in _tlist)
            {
                double converteditem = item.ToOADate();
                __tlist.Add(converteditem);
            }
            tlist = __tlist;
}

XAML：

unique_window.xaml

<Window x:Class="PP1.unique_window"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local="clr-namespace:PP1" xmlns:d3="clr-namespace:InteractiveDataDisplay.WPF;assembly=InteractiveDataDisplay.WPF"
    mc:Ignorable="d"
    Title="{Binding Path=myTitle}" Height="759.7" Width="1130">

<Grid>
    <Canvas Grid.ColumnSpan="3">
        <d3:Chart BottomTitle="Date" LeftTitle="Temp" Height="287" Width="513" Canvas.Left="565" Canvas.Top="378">
            <d3:LineGraph x:Name="linegrapht" Description="linegraph" Stroke="DarkRed" StrokeThickness="3"/>
        </d3:Chart>
        <d3:Chart BottomTitle="Date" LeftTitle="Hum" Height="129" Width="412" Canvas.Left="543" Canvas.Top="71">
            <d3:LineGraph x:Name="linegraphh" Description="linegraph" Stroke="Blue" StrokeThickness="3"/>
        </d3:Chart>
    </Canvas>

</Grid>

如果不将List tlist转换为双精度类型，则会出现此异常。

如何使DateTime类型的X轴或具有可读日期的浮点数而没有无效的强制转换例外？