extension-method-wrappers.md

The syntax for directly using connected properties is a bit awkward. One way to make it less awkward for end-users is to wrap connected property access into extension methods, as such:

// Represents a piece of data that has been read out of a file.
// We want to connect a property containing the source line number.
public class Token { .. }

// Allow access to the connected property via extension methods.
using Nito.ConnectedProperties;
public static class TokenExtensions
{
  private const string SourceLineNumber = Guid.NewGuid().ToString("N");

  public static int GetSourceLineNumber(this Token token) =>
      ConnectedProperty.Get(token, SourceLineNumber);

  public static void SetSourceLineNumber(this Token token, int lineNumber) =>
      ConnectedProperty.Set(token, SourceLineNumber, lineNumber);
}

The end-user then has GetSourceLineNumber and SetSourceLineNumber extension methods that they may use, instead of having to use the Connected Properties library directly.