HelloWorld/Eight/UpdateWindow.xaml

<Window x:Class="Eight.UpdateWindow"
        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:Eight"
        mc:Ignorable="d"
        Title="Обновление цен" Height="250" Width="300" ResizeMode="NoResize">
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition/>
            <ColumnDefinition/>
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
            <RowDefinition/>
            <RowDefinition/>
        </Grid.RowDefinitions>
        <TextBlock Margin="5" Text="Цена" Style="{StaticResource RightSideTextBlock}"></TextBlock>
        <TextBox Margin="5" Style="{StaticResource VerticalTextBox}" Grid.Column="1" Name="TbCost"></TextBox>
        <Button Grid.Column="1" Grid.Row="1" Style="{StaticResource DefaultButton}" Name="BtnSubmit" Click="BtnSubmit_Click"
                Content="Подтвердить" Margin="5"></Button>
    </Grid>
</Window>