using System.Globalization;using System.IO;using System.Windows.Controls;namespace VBASync.WPF{public class FilePathValidationRule : ValidationRule{public override ValidationResult Validate(object value, CultureInfo cultureInfo)=> new ValidationResult(string.IsNullOrEmpty(value as string) || File.Exists(value as string), null);}public class FolderPathValidationRule : ValidationRule{public override ValidationResult Validate(object value, CultureInfo cultureInfo)=> new ValidationResult(string.IsNullOrEmpty(value as string) || Directory.Exists(value as string), null);}}