Generic equality interfaces

Lecture overview -- Keyboard shortcut: 'u'

Previous page: Generic interfaces: IComparable<T> -- Keyboard shortcut: 'p'

Next page: Generic Classes and Inheritance -- Keyboard shortcut: 'n'

Annotated slide -- Keyboard shortcut: 't'

Generic Types and Methods - slide 15 : 21

Generic equality interfaces

The generic interface IEquatable<T> prescribes an Equals operation, and as such it is more fundamental than the interface IComparable<T>.

The generic interface IEqualityComparer<T> prescribes both Equals and GetHashCode.

A reproduction of the generic interface IEquatable<T>.

A reproduction of the generic interface IEqualityComparer<T>.

Practical use of these interfaces
- Collection classes of T elements often need to know if two elements of type T are equal to each other
- From T it is possible to request a default equality comparer, which implements IEqualityComparer<T>