Value conversion with IValueConverter in WPF

<Window x:Class="WpfTutorialSamples.DataBinding.ConverterSample"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:WpfTutorialSamples.DataBinding"
        Title="ConverterSample" Height="140" Width="250">
    <Window.Resources>
        <local:YesNoToBooleanConverter x:Key="YesNoToBooleanConverter" />
    </Window.Resources>
    <StackPanel Margin="10">
        <TextBox Name="txtValue" />
        <WrapPanel Margin="0,10">
            <TextBlock Text="Current value is: " />
            <TextBlock Text="{Binding ElementName=txtValue, Path=Text, Converter={StaticResource YesNoToBooleanConverter}}"></TextBlock>
        </WrapPanel>
        <CheckBox IsChecked="{Binding ElementName=txtValue, Path=Text, Converter={StaticResource YesNoToBooleanConverter}}" Content="Yes" />
    </StackPanel>
</Window>
using System;
using System.Windows;
using System.Windows.Data;

namespace WpfTutorialSamples.DataBinding
{
    public partial class ConverterSample : Window
    {
        public ConverterSample()
        {
            InitializeComponent();
        }
    }

    public class YesNoToBooleanConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            switch(value.ToString().ToLower())
            {
                case "yes":
                case "oui":
                    return true;
                case "no":
                case "non":
                    return false;
            }
            return false;
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if(value is bool)
            {
                if((bool)value == true)
                    return "yes";
                else
                    return "no";
            }
            return "no";
        }
    }
}

References
https://wpf-tutorial.com/data-binding/value-conversion-with-ivalueconverter/