.Net Framework

Types behaving badly

14 Apr 2018

At the opening of this series I wrote about how a correct implementation of equality is essential for the correct behaviour of many fundamental .NET types - including List, HashSet and Dictionary. Here’s an example to show how they can break.

Implementing Value Equality

7 Apr 2018

equality

dotnet

Building on our implementation of entity equality, we are now in a position to implement value equality. This is more complex because it tends to have a greater number of factors to consider.

Implementing Entity Equality

31 Mar 2018

equality

dotnet

Now that we’ve talked about the importance of implementing equality, the different kinds of equality, and about the contracts required of our implementations, we can get down to actually writing some code.

Equality and GetHashCode

24 Mar 2018

equality

dotnet

After symmetry, another aspect of the equality contract is .GetHashCode(). When you first override .Equals(object), the C# compiler will helpfully remind you that you must also override .GetHashCode().

Types of Equality

10 Mar 2018

equality

dotnet

Having established the importance of equality in .NET, we can look at the different kinds of equality that you might encounter. There are three - Reference, Value and Entity equality.

Types behaving badly

Implementing Value Equality

Implementing Entity Equality

Equality and GetHashCode

Types of Equality

Older posts