NullRefrenceException使用Datagrid的DataContext - WPF C＃

Question

我正在尝试创建一个允许您选择文件夹并在DataGrid上显示其文件信息的Lil工具。但是对于一个未知的原因，我不能将我的对象列表作为DataGrid的DataContext属性。

XAML代码：

<Window x:Class="WPFFileExplorer.MainWindow"
    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:WPFFileExplorer"
    mc:Ignorable="d"
    Title="MainWindow" Height="350" Width="525">
<Window.Resources>
    <Style TargetType="Button">
        <Setter Property="Background"
                Value="Aqua" />
        <Setter Property="FontSize"
                Value="26" />
    </Style>

</Window.Resources>
<Window.Background>
    <LinearGradientBrush EndPoint="0.5,1" MappingMode="RelativeToBoundingBox" StartPoint="0.5,0">
        <GradientStop Color="#FF04B1CD"/>
        <GradientStop Color="#FF66FB21" Offset="1"/>
    </LinearGradientBrush>
</Window.Background>
<Grid>
    <Grid.RowDefinitions>
        <RowDefinition Height="60*"/>
        <RowDefinition Height="201*"/>
        <RowDefinition Height="58*"/>
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="76*"/>
        <ColumnDefinition Width="182*"/>
        <ColumnDefinition Width="182*"/>
        <ColumnDefinition Width="77*"/>
    </Grid.ColumnDefinitions>

    <TextBlock Text="File Explorer" Grid.Column="1" Grid.ColumnSpan="2" TextAlignment="Center" FontSize="42" FontFamily="Segoe UI Black" />
    <DataGrid Name="fileslst" DataContext="{Binding}" Grid.Column="1" AutoGenerateColumns="False" Grid.ColumnSpan="2" Margin="30,0.441,30,0" Grid.Row="1">

    </DataGrid>
</Grid>

C＃代码：

namespace WPFFileExplorer
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
public partial class MainWindow : Window
{

    public MainWindow()
    {

        List<Filei> files = new List<Filei>();
        FolderBrowserDialog fbd = new FolderBrowserDialog();
        if (fbd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
        {
            fileslst.DataContext = files;
            DataGridTextColumn dgname = new DataGridTextColumn { Header = "Name"};
            dgname.Binding = new System.Windows.Data.Binding("Name");
            DataGridTextColumn dgpath = new DataGridTextColumn { Header = "Path" };
            dgpath.Binding = new System.Windows.Data.Binding("Path");
            DataGridTextColumn dgct = new DataGridTextColumn { Header = "Creation Time" };
            dgct.Binding = new System.Windows.Data.Binding("CreationTime");

            fileslst.Columns.Add(dgname);
            fileslst.Columns.Add(dgpath);
            fileslst.Columns.Add(dgct);

            string[] filesarr = Directory.GetFiles(fbd.SelectedPath);
            foreach (string s in filesarr)
            {
                FileInfo fi = new FileInfo(s);
                DateTime ct = fi.CreationTime;
                Filei f = new Filei() { Name = fi.Name, Root = s, CreationTime = ct };

            }


        }
    }
}

public class Filei
{
    public override string ToString()
    {
        return string.Format("Name: {0} \n Path: {1} \n Creation Time: {3}", Name, Root, CreationTime);
    }
    public string Name { get; set; }
    public string Root { get; set; }
    public DateTime CreationTime { get; set; }
}

}

非常感谢帮助者！