gethashcode

This test is failing : var hashCode = new { CustomerId = 3354, ServiceId = 3, CmsThematicId = (int?)605, StartDate = (DateTime?)new DateTime(2013, 1, 5), EndDate = (DateTime?)new DateTime(2013, 1, 6) }.GetHashCode(); var hashCode2 = new { CustomerId = 1210, ServiceId = 3, CmsThematicId = (int?)591, StartDate = (DateTime?)new DateTime(2013, 3, 31), EndDate = (DateTime?)new DateTime(2013, 4, 1) }.GetHashCode(); Assert.AreNotEqual(hashCode, hashCode2); Can you tell me why ? Samuel Neff It's kinda amazing you found this coincidence. Anonymous classes have a generated GetHashCode() method that

I came to this site searching for object comparison in Dictionary, and i came to know that overriding GetHashCode and Equals are a must for doing object comparison in C#. Here is a piece of code that i have been trying to solve out, using FOREACH iteration Method. But my Boss says to do the same without using any iteration(maybe by using containskey or containsvalue method), due to performance issues. Any help is highly welcome.. public class employee { public string empname { get; set; } public string location { get; set; } public double kinid { get; set; } public double managerKin { get; set

I was wondering whether the .Net HashSet<T> is based completely on hash codes or whether it uses equality as well? I have a particular class that I may potentially instantiate millions of instances of and there is a reasonable chance that some hash codes will collide at that point. I'm considering using HashSet's to store some instances of this class and am wondering if it's actually worth doing - if the uniqueness of an element is only determined on its hash code then that's of no use to me for real applications MSDN documentation seems to be rather vague on this topic - any enlightenment

Folks, here's a thorny problem for you! A part of the TickZoom system must collect instances of every type of object into a Dictionary<> type. It is imperative that their equality and hash code be based on the instance of the object which means reference equality instead of value equality. The challenge is that some of the objects in the system have overridden Equals() and GetHashCode() for use as value equality and their internal values will change over time. That means that their Equals and GetHashCode are useless. How to solve this generically rather than intrusively? So far, We created a

How do I deal with null fields in GetHashCode function? Module Module1 Sub Main() Dim c As New Contact Dim hash = c.GetHashCode End Sub Public Class Contact : Implements IEquatable(Of Contact) Public Name As String Public Address As String Public Overloads Function Equals(ByVal other As Contact) As Boolean _ Implements System.IEquatable(Of Contact).Equals Return Name = other.Name AndAlso Address = other.Address End Function Public Overrides Function Equals(ByVal obj As Object) As Boolean If ReferenceEquals(Me, obj) Then Return True If TypeOf obj Is Contact Then Return Equals(DirectCast(obj,

The program was working with this implementation: class Instrument { public string ClassCode { get; set; } public string Ticker { get; set; } public override string ToString() { return " ClassCode: " + ClassCode + " Ticker: " + Ticker + '.'; } } But because I need to use Instrument in Dictionary I've decided to implement equals/hashcode: class Instrument { public string ClassCode { get; set; } public string Ticker { get; set; } public override string ToString() { return " ClassCode: " + ClassCode + " Ticker: " + Ticker + '.'; } public override bool Equals(object obj) { if (obj == null) return