AvaloniaApp/AvaloniaApplication2/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="1500" d:DesignHeight="450"
        x:Class="AvaloniaApplication2.MainWindow"
        Title="AvaloniaApplication2" FontSize="15">
	<Grid>
		<StackPanel Name="WritePanel" HorizontalAlignment="Center" IsVisible="True">
			<StackPanel Orientation ="Vertical">
				<StackPanel Orientation ="Horizontal">
					<StackPanel>
						<TextBlock Margin="0,20,20,0">Введите фамилию:</TextBlock>
						<TextBox Name ="tbLastName" Margin="0,0,20,0"></TextBox>
					</StackPanel>
					<StackPanel>
						<TextBlock Margin="0,20,20,0">Введите имя:</TextBlock>
						<TextBox Name ="tbFirstName" Margin="0,0,20,0"></TextBox>
					</StackPanel>
					<StackPanel>
						<TextBlock Margin="0,20,0,0">Введите отчество:</TextBlock>
						<TextBox Name ="tbPatronymic"></TextBox>
					</StackPanel>
				</StackPanel>
				<StackPanel Orientation="Horizontal">
					<StackPanel>
						<TextBlock Margin="0,20,30,0">Введите день рождения:</TextBlock>
						<TextBox Name ="tbBirthDay" Margin="0,0,30,0"></TextBox>
					</StackPanel>
					<StackPanel>
						<TextBlock Margin="0,20,0,0">Выберите месяц рождения:</TextBlock>
						<StackPanel>
							<ComboBox Name ="cbBirthMonth" SelectedIndex="0" Width="200">
								<ComboBoxItem>Январь</ComboBoxItem>
								<ComboBoxItem>Февраль</ComboBoxItem>
								<ComboBoxItem>Март</ComboBoxItem>
								<ComboBoxItem>Апрель</ComboBoxItem>
								<ComboBoxItem>Май</ComboBoxItem>
								<ComboBoxItem>Июнь</ComboBoxItem>
								<ComboBoxItem>Июль</ComboBoxItem>
								<ComboBoxItem>Август</ComboBoxItem>
								<ComboBoxItem>Сентябрь</ComboBoxItem>
								<ComboBoxItem>Октябрь</ComboBoxItem>
								<ComboBoxItem>Ноябрь</ComboBoxItem>
								<ComboBoxItem>Декабрь</ComboBoxItem>
							</ComboBox>
						</StackPanel>
					</StackPanel>
				</StackPanel>
				<StackPanel Orientation="Horizontal">
					<StackPanel>
						<TextBlock  Margin="0,20,0,0">Введите год рождения:</TextBlock>
						<TextBox Name ="tbBirthYear"></TextBox>
					</StackPanel>
					<StackPanel>
						<TextBlock  Margin="40,20,0,0">Выберите пол:</TextBlock>
						<StackPanel Orientation="Horizontal">
							<RadioButton Margin="40,0,10,0" GroupName="Genders" Name="GenderM" Content="Мужской" IsChecked="True"/>
							<RadioButton GroupName="Genders" Content="Женский" Name="GenderF" IsChecked="False"/>
						</StackPanel>
					</StackPanel>
				</StackPanel>
				<StackPanel Orientation="Vertical">
					<TextBlock Margin="0,20,0,0">Введите номер телефона:</TextBlock>
					<TextBox Name="tbPhone" Width="415" HorizontalAlignment="Left"></TextBox>
				</StackPanel>
				<StackPanel Orientation="Horizontal">
					<TextBlock Name="tErrMsg" Foreground="Red" Margin="0,15,0,0"></TextBlock>
				</StackPanel>
				<StackPanel>
					<Button Margin="0,20,0,0" HorizontalAlignment="Center" Click="WriteFile">Записать данные</Button>
					<Button Margin="0,20,0,0" HorizontalAlignment="Center" Click="ShowUsers">Показать пользователей</Button>
				</StackPanel>
			</StackPanel>
		</StackPanel>
		<StackPanel Name="UsersPanel" HorizontalAlignment="Center" IsVisible="False">
			<Button Click="ClickBack" Margin="0,20,0,0">Назад</Button>
		</StackPanel>
	</Grid>
</Window>