Today, I’m proud to share with you my very first article available on CodeProject. This article presents a technique which can be used in order to add validation in a WPF MVVM application based on attribute. Basically, it means that you can write validation logic like that (notice the attribute associated to this property):

[Required(ErrorMessage = "Field 'FirstName' is required.")]
public string FirstName
{
    get
    {
        return this.firstName;
    }
    set
    {
        this.firstName = value;
        this.OnPropertyChanged("FirstName");
    }
}

Of course the article comes with a nice demo application:

You can read the full article here: Attributes-based validation in a WPF MVVM application