SearchVulnerabilities/WpfApp1/AddOrUpdateClient.xaml

<Window x:Class="WpfApp1.AddOrUpdateClient"
        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:WpfApp1"
        mc:Ignorable="d"
        Title="AddOrUpdateClient" Height="450" Width="800" FontFamily="Comic Sans MS" FontSize="16">
    <Grid>
        <StackPanel VerticalAlignment="Center">
            <TextBlock Text="Добавление клиента" HorizontalAlignment="Center" FontWeight="Bold" FontSize="24"/>
            <GroupBox Header="Имя" Margin="5">
                <TextBox Name="tbName"/>
            </GroupBox>
            <GroupBox Header="Фамилия" Margin="5">
                <TextBox Name="tbSurname"/>
            </GroupBox>
            <GroupBox Header="Телефон" Margin="5">
                <TextBox Name="tbPhoneNumber"/>
            </GroupBox>
            <GroupBox Header="E-mail" Margin="5">
                <TextBox Name="tbE_mail"/>
            </GroupBox>
            <Button Name="btnSave" Margin="5" Content="Сохранить" Height="40" Width="200" Click="btnSave_Click"/>
        </StackPanel>
    </Grid>
</Window>