WPF MVVM Folder dialog

FolderDialogBehavior.cs

using System.Linq;
using System.Reflection;
using System.Windows;
using System.Windows.Forms;
using System.Windows.Interactivity;
using Button = System.Windows.Controls.Button;

namespace FolderDialog
{
    public class FolderDialogBehavior : Behavior<Button>
    {
        public string SetterName { get; set; }

        protected override void OnAttached()
        {
            base.OnAttached();
            AssociatedObject.Click += OnClick;
        }

        protected override void OnDetaching()
        {
            AssociatedObject.Click -= OnClick;
        }

        private void OnClick(object sender, RoutedEventArgs e)
        {
            var dialog = new FolderBrowserDialog();
            var result = dialog.ShowDialog();
            if (result == DialogResult.OK && AssociatedObject.DataContext != null)
            {
                var propertyInfo = AssociatedObject.DataContext.GetType().GetProperties(BindingFlags.Instance | BindingFlags.Public)
                    .Where(p => p.CanRead && p.CanWrite)
                    .First(p => p.Name.Equals(SetterName));

                propertyInfo.SetValue(AssociatedObject.DataContext, dialog.SelectedPath, null);
            }
        }
    }
}

MainViewModel.cs

using System.ComponentModel;

namespace FolderDialog
{
    public class MainViewModel: INotifyPropertyChanged
    {
        private string _folderName;

        public string FolderName
        {
            get { return _folderName; }
            set
            {
                _folderName = value;
                OnPropertyChanged("FolderName");
            }
        }

        #region Implementation of INotifyPropertyChanged

        public event PropertyChangedEventHandler PropertyChanged;

        protected virtual void OnPropertyChanged(string propertyName)
        {
            OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
        }

        protected virtual void OnPropertyChanged(PropertyChangedEventArgs args)
        {
            var handler = PropertyChanged;
            if (handler != null)
                handler(this, args);
        }

        #endregion
    }
}

MainWindow.xaml

<Window x:Class="FolderDialog.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:FolderDialog="clr-namespace:FolderDialog"
        xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
        Title="MainWindow" Height="350" Width="525"
        >
    <Window.DataContext>
        <FolderDialog:MainViewModel></FolderDialog:MainViewModel>
    </Window.DataContext>
    <Grid>
        <StackPanel>
            <TextBlock Text="{Binding FolderName}"/>
            <Button Content="Select Folder">
                <i:Interaction.Behaviors>
                    <FolderDialog:FolderDialogBehavior SetterName="FolderName"/>
                </i:Interaction.Behaviors>
            </Button>
        </StackPanel>
    </Grid>
</Window>