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IEqualityComparer<T>

As explained in Pro ASP.NET Core 7, Tenth Edition

IEqualityComparer<T> is a .NET interface that defines equality comparison and hash-code operations for values of type T.

IEqualityComparer<T> defines equality and hash-code operations for values of type T. In unit tests, xUnit.net Assert.Equal uses it to compare objects created from custom classes. section 6.3.5

Comparing Product objects

A controller test compares expected Product values with the Index action model by matching each product's Name and Price through Comparer.Get<Product>(...).

How Pro ASP.NET Core 7, Tenth Edition covers it

How deep it goes
Defines a lambda-backed implementation and hash-code fallback, but does not explain equality contracts or framework internals.
Examples
Uses Product objects whose Name and Price values are compared in a HomeController test.
What it assumes
Assumes familiarity with custom classes, unit tests, lambda expressions, and xUnit.net assertions.
What you can do after
Apply it via xUnit.net Assert.Equal to compare custom objects using test-specific lambda expressions.
How it connects
Connects custom classes, xUnit.net Assert.Equal, lambda expressions, controllers, and unit testing.
Cover of Pro ASP.NET Core 7, Tenth Edition
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Related concepts

This explainer was generated by Manning's knowledge graph from the text of Pro ASP.NET Core 7, Tenth Edition. The section links point to the parts of the book it draws on.