MainWindow.xaml

<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:WpfSample"
        xmlns:Wpf="clr-namespace:Microsoft.Web.WebView2.Wpf;assembly=Microsoft.Web.WebView2.Wpf" x:Name="window" x:Class="WpfSample.MainWindow"
        mc:Ignorable="d"
        Title="Ookii.CommandLine WPF Sample" Height="450" Width="800">
    <Grid Margin="6,6,6,6">
        <Grid.Resources >
            <Style TargetType="TextBox" >
                <Setter Property="Margin" Value="5,5,5,5" />
                <Setter Property="Padding" Value="5,5,5,5" />
            </Style>
            <Style TargetType="Label" >
                <Setter Property="Margin" Value="5,5,5,5" />
            </Style>
            <Style TargetType="CheckBox" >
                <Setter Property="Margin" Value="5,10,5,5" />
            </Style>
            <Style TargetType="ListBox" >
                <Setter Property="Margin" Value="5,5,5,5" />
                <Setter Property="Padding" Value="5,5,5,5" />
            </Style>
            <Style TargetType="Button" >
                <Setter Property="Margin" Value="5,5,5,5" />
                <Setter Property="Padding" Value="5,5,5,5" />
            </Style>
        </Grid.Resources>        
        <Grid.RowDefinitions>
            <RowDefinition Height="auto"/>
            <RowDefinition Height="auto"/>
            <RowDefinition Height="auto"/>
            <RowDefinition Height="auto"/>
            <RowDefinition Height="auto"/>
            <RowDefinition Height="auto"/>
            <RowDefinition Height="auto"/>
            <RowDefinition Height="*"/>
            <RowDefinition Height="auto"/>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="auto"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>
        <Label Grid.Row="0" Grid.Column="0">Source</Label>
        <TextBox Grid.Row="0" Grid.Column="1" IsReadOnly="True" Text="{Binding Arguments.Source, ElementName=window}" />
        <Label Grid.Row="1" Grid.Column="0">Destination</Label>
        <TextBox Grid.Row="1" Grid.Column="1" IsReadOnly="True" Text="{Binding Arguments.Destination, ElementName=window}" />
        <Label Grid.Row="2" Grid.Column="0">OperationIndex</Label>
        <TextBox Grid.Row="2" Grid.Column="1" IsReadOnly="True" Text="{Binding Arguments.OperationIndex, ElementName=window}" />
        <Label Grid.Row="3" Grid.Column="0">Date</Label>
        <TextBox Grid.Row="3" Grid.Column="1" IsReadOnly="True" Text="{Binding Arguments.Date, ElementName=window, TargetNullValue=(null)}" />
        <Label Grid.Row="4" Grid.Column="0">Count</Label>
        <TextBox Grid.Row="4" Grid.Column="1" IsReadOnly="True" Text="{Binding Arguments.Count, ElementName=window}" />
        <Label Grid.Row="5" Grid.Column="0">Verbose</Label>
        <CheckBox Grid.Row="5" Grid.Column="1" IsEnabled="False" IsChecked="{Binding Arguments.Verbose, ElementName=window}" />
        <Label Grid.Row="6" Grid.Column="0">Day</Label>
        <TextBox Grid.Row="6" Grid.Column="1" IsReadOnly="True" Text="{Binding Arguments.Day, ElementName=window, TargetNullValue=(null)}" />
        <Label Grid.Row="7" Grid.Column="0">Values</Label>
        <ListBox Grid.Row="7" Grid.Column="1" ItemsSource="{Binding Arguments.Values, ElementName=window}" />
        <Button x:Name="_helpButton" Grid.Row="8" Grid.Column="1" HorizontalAlignment="Right" Content="Help" Click="_helpButton_Click"/>
    </Grid>
</Window>