How to validate child objects by implementing IDataErrorInfo on parent class

Question

I am developing a WPF Application using MVVM Architecture. I am an amateur in WPF so bear with me..

I have two model classes. Parent class has an object of another (

Answer 1

You can absolutely implement IDataErrorInfo on a base class using Validation Application Block. Here is an article that describes how to. The code basically comes down to this:

public abstract class DataErrorInfo : IDataErrorInfo
{
    string IDataErrorInfo.Error
    {
        get { return string.Empty; }
    }

    string IDataErrorInfo.this[string columnName]
    {
        get
        {
            var prop = this.GetType().GetProperty(columnName);
            return this.GetErrorInfo(prop); 
        }
    }

    private string GetErrorInfo(PropertyInfo prop)
    {
        var validator = this.GetPropertyValidator(prop);

        if (validator != null)
        {
           var results = validator.Validate(this);

           if (!results.IsValid)
           {
              return string.Join(" ",
                  results.Select(r => r.Message).ToArray());
           }
        }

        return string.Empty;
    }

    private Validator GetPropertyValidator(PropertyInfo prop)
    {
        string ruleset = string.Empty;
        var source = ValidationSpecificationSource.All;
        var builder = new ReflectionMemberValueAccessBuilder();
        return PropertyValidationFactory.GetPropertyValidator(
            this.GetType(), prop, ruleset, source, builder);
    }
}

You can use this abstract class add validation behavior to your entities by inheriting from it:

public partial class Customer : DataErrorInfo
{
}