Library vs app .csproj, semantic versioning

using System;
using System.Reflection;

// Simple demo: read the assembly version at runtime.
// In a packed library, this reflects the version consumers see.
public class Program
{
  public static void Main(string[] args)
  {
    Version v = Assembly.GetExecutingAssembly().GetName().Version;
    Console.WriteLine("Assembly version: " + (v == null ? "unknown" : v.ToString()));
  }
}

using System;

// Minimal SemVer (MAJOR.MINOR.PATCH) parsing and comparison.
// Ignores prerelease/build metadata for simplicity (good enough for beginners).
public class SemVer : IComparable<SemVer>
{
  public int Major;
  public int Minor;
  public int Patch;

  public static bool TryParse(string s, out SemVer v)
  {
    v = null;
    if (string.IsNullOrEmpty(s)) return false;
    string[] parts = s.Split('.');
    if (parts.Length < 3) return false;
    int a, b, c;
    if (!int.TryParse(parts[0], out a)) return false;
    if (!int.TryParse(parts[1], out b)) return false;
    if (!int.TryParse(parts[2], out c)) return false;
    v = new SemVer { Major = a, Minor = b, Patch = c };
    return true;
  }

  public int CompareTo(SemVer other)
  {
    if (other == null) return 1;
    if (Major != other.Major) return Major.CompareTo(other.Major);
    if (Minor != other.Minor) return Minor.CompareTo(other.Minor);
    return Patch.CompareTo(other.Patch);
  }

  public override string ToString()
  {
    return Major + "." + Minor + "." + Patch;
  }
}

public class Program
{
  public static void Main(string[] args)
  {
    SemVer a, b;
    if (SemVer.TryParse("1.4.2", out a) && SemVer.TryParse("1.5.0", out b))
    {
      int cmp = a.CompareTo(b);
      Console.WriteLine(a + " vs " + b + " -> " + (cmp < 0 ? "older" : (cmp > 0 ? "newer" : "equal")));
    }
  }
}