AvaloniaStart/PracticAvalonia/MainWindow.axaml

<Window xmlns="https://github.com/avaloniaui"
        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"
        mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
        x:Class="PracticAvalonia.MainWindow"
        Title="PracticAvalonia"
		MinWidth="600"
		MinHeight="350">
	<ScrollViewer>
		<Grid HorizontalAlignment="Center">
			<StackPanel HorizontalAlignment="Center" Name="WritePanel">
				<TextBlock Text="Введите персональные данные:" Margin="5"/>
				<TextBox Name="tbSurname" Watermark="Фамилия" Margin="5"/>
				<TextBox Name="tbName" Watermark="Имя" Margin="5"/>
				<TextBox Name="tbPatronymic" Watermark="Отчество" Margin="5"/>
				<StackPanel Orientation="Horizontal">
					<TextBlock Text="Пол:" Margin="5"/>
					<RadioButton Name="rbM" Margin="5" Content="Мужской"/>
					<RadioButton Name="rbG" Margin="5" Content="Женский"/>
				</StackPanel>
				<StackPanel Orientation="Horizontal">
					<TextBlock Text="Номер телефона:" Margin="5"/>
					<TextBox Name="tbTelephone" Watermark="8(XXX)XXX-XX-XX" MinWidth="150"/>
				</StackPanel>
				<StackPanel Orientation="Horizontal" >
					<TextBlock Text="Дата рождения:" Margin="5"/>
					<NumericUpDown Name="tbDay"
								   FormatString="0"
								   Value="1"
								   Minimum="1"
								   Maximum="31"
								   Margin="5"
								   Width="150"/>
					<StackPanel>
						<ComboBox Name="cbMonth" SelectedIndex="0" Margin="5" Width="150">
							<ComboBoxItem IsEnabled="false" Content="Месяц"/>
							<ComboBoxItem Content="Январь"/>
							<ComboBoxItem Content="Февраль"/>
							<ComboBoxItem Content="Март"/>
							<ComboBoxItem Content="Апрель"/>
							<ComboBoxItem Content="Май"/>
							<ComboBoxItem Content="Июнь"/>
							<ComboBoxItem Content="Июль"/>
							<ComboBoxItem Content="Август"/>
							<ComboBoxItem Content="Сентябрь"/>
							<ComboBoxItem Content="Октябрь"/>
							<ComboBoxItem Content="Ноябрь"/>
							<ComboBoxItem Content="Декабрь"/>
						</ComboBox>
					</StackPanel>
					<NumericUpDown Name="tbYear"
								   FormatString="0000"
								   Value="1910"
								   Minimum="1910"
								   Maximum="2024"
								   Margin="5"
								   Width="150"/>
				</StackPanel>
				<StackPanel HorizontalAlignment="Center" Orientation="Horizontal">
					<Button
						Content="Записать в файл"
						Click="WriteFile"
						Margin="10"
						FontSize="18"
						Background="Plum"
						Foreground="Black"/>
					<Button
						Content="Прочитать из файла"
						Click="ReadFile"
						Margin="10"
						FontSize="18"
						Background="Plum"
						Foreground="Black"/>
				</StackPanel>
				<TextBlock HorizontalAlignment="Center"
						   Name="ShowMessage"
						   Foreground="Red"
						   FontSize="18"/>
			</StackPanel>
			<StackPanel HorizontalAlignment="Center" Name="ReadPanelControl" IsVisible="False">
				<Button HorizontalAlignment="Center"
							Content="Назад"
							Click="Back"
							Margin="10"
							FontSize="18"
							Background="Plum"
							Foreground="Black"/>
				<StackPanel HorizontalAlignment="Center" Name="ReadPanel" IsVisible="False">
				</StackPanel>
			</StackPanel>
		</Grid>
	</ScrollViewer>
</Window>