Inheritance vs. interface in C# [duplicate]

Answer 1

Honestly, do both.

public interface IScraper
{
  string ScrapeDate(string url);
}

public abstract class Scraper : IScraper
{
  public string ScrapeDate(string url)
  {
    // default implementation
  }
}

There's advantages either way, but those are difficult to quantify without knowing more about your requirements. However, there's no reason you can't do both. Having an interface for your class makes it mockable for testing purposes as well.

Something else to consider though; if the functionality for each of your derived classes are similar enough, it may be easier to simply have a single class that takes parameters to the constructor.