When is it necessary to override Equals() in a .NET class?

Posted by Alex Angas on Stack Overflow See other posts from Stack Overflow or by Alex Angas
Published on 2010-06-07T23:19:09Z Indexed on 2010/06/07 23:22 UTC
Read the original article Hit count: 150

Filed under:

.NET

|

equality

.NET contains its own equality comparison functionality, however I don't really understand how it works.

If the desired Equals() and == behaviour is to verify that every field of an object is equal to every field of another object, is it necessary to override Equals() with a method that does this explicitly?

© Stack Overflow or respective owner

Related posts about .NET

Apt-Get Update: failure to fetch; can't connect to any sources

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I realize there are dozens of "apt-get update: failure to fetch" questions (I read through all I could find), but my present circumstance is unique to 12.04 and it affects all sources; not just launchpad. Additionally, I've tried several different servers in Europe and the U.S. as well as the "main… >>> More
12.04: Apt-Get Update: failure to fetch; can't connect to any sources

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I realize there are dozens of "apt-get update: failure to fetch" questions (I read through all I could find), but my present circumstance is unique to 12.04 and it affects all sources; not just launchpad. Additionally, I've tried several different servers in Europe and the U.S. as well as the "main… >>> More
What's New in ASP.NET 4

as seen on Geeks with Blogs - Search for 'Geeks with Blogs'
The .NET Framework version 4 includes enhancements for ASP.NET 4 in targeted areas. Visual Studio 2010 and Microsoft Visual Web Developer Express also include enhancements and new features for improved Web development. This document provides an overview of many of the new features that are included… >>> More
.NET Reflector 6, .NET Reflector Pro, TestDriven.NET, .NET 4.0 and Mono

as seen on Simple Talk - Search for 'Simple Talk'
By now you may well have noticed that .NET Reflector 6 and .NET Reflector Pro are out in the wild. The official launch happened today, although we actually put the software out last Thursday as part of a phased release plan to ensure that everything went smoothly today which, so far, it seems to have… >>> More
Redmine on Apache2 with Passenger issue

as seen on Server Fault - Search for 'Server Fault'
I installed Redmine and run it in Apache2 with the Passenger module. Apache2 boots, Passenger module gets loaded and the Redmine welcome page is shown, however when trying to login or navigate to other parts of the Redmine site, the browser keeps loading and loading and loading forever, although the… >>> More

Related posts about equality

Compare equality of char[] in C

as seen on Stack Overflow - Search for 'Stack Overflow'
I have two variables: char charTime[] = "TIME"; char buf[] = "SOMETHINGELSE"; I want to check if these two are equal... using charTime == buf doesn't work. What should I use, and can someone explain why using == doesn't work? Would this action be different in C and C++? >>> More
double.NaN Equality in MS Test

as seen on Stack Overflow - Search for 'Stack Overflow'
Why am I getting this result? [TestMethod] public void nan_test() { Assert.AreEqual(1, double.NaN, 1E-1); <-- Passes Assert.AreEqual(1, double.NaN); <-- Fails } What difference does the delta have in asserting NaN equals a number? Surely it should always return false. I am aware… >>> More
JSF Testing for Enum equality

as seen on Stack Overflow - Search for 'Stack Overflow'
Is it possible to test for enum equality in JSF? i.e. <h:outputText value="text" rendered="#{myBean.enum==BeanEnum.enum1}"/> >>> More
Django comparing model instances for equality

as seen on Stack Overflow - Search for 'Stack Overflow'
I understand that, with a singleton situation, you can perform such an operation as: spam == eggs and if spam and eggs are instances of the same class with all the same attribute values, it will return True. In a Django model, this is natural because two separate instances of a model won't ever… >>> More
How to check for DOM equality with jQuery?

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm basically building a simple list, and one of the items in the list is selected. I'm accomplishing this by having a "selected" class applied to whichever item I want to have selected. I have two buttons that go forward and backward which traverse this list. However, when the user gets to the… >>> More