title: How do I check if two Objects are equal in terms of their properties only without breaking the existing Object.Equals()?
body: <p>Basically, GethashCode is different even though they contain the SAME values for the properties... so why is the default to return diff hashcodes?</p>
  
  <pre><code>public class User
  {
      public Int32 Id { get; set; }
      public String Username { get; set; }
  }
  
  User a = new User();
  a.Id = 1;
  a.Username = "Hello";
  
  User b = new User();
  b.Id = 1;
  b.Username = "Hello";
  
  Console.WriteLine("Hash A: {0} | Hash B: {1}", a.GetHashCode(), b.GetHashCode());
  //Hash A: 37121646 | Hash B: 45592480 &lt;-- these values change each time I rerun the app?
  </code></pre>
  
  <p>Is there a more proper way to make it so I don't break how Object.Equals works for my objects, but am still able to have my own equality checking based on the parameter values?</p>
  
  <p>The reason I ask is because I have a service: <code>SynchronizeUsers()</code> which downloads an array of users. Instead of clearing out my cache of users, I'd rather just update the ones that need to be updated, remove the ones that the synch says to, and add the new ones. But, I can't just do Object.Equals() on these objects.</p>