What is a Comparer C#?

Introduction. Objects Comparer is an object-to-object comparer that allows you to compare objects recursively member by member and defines custom comparison rules for certain properties, fields, or types. Objects Comparer can be considered as ready to use a framework or as an idea for similar solutions.

What is the difference between IComparer and IComparable in C#?

IComparer compares two objects that it’s given. IComparable is implemented by the object that is being compared, for the purpose of comparing with another one of itself.

Can you compare objects in C#?

In C# objects can be compared with the == operator, with the Equals(Object) member, with the Object.

What is the Comparer class used for?

Comparer holds an actual compare method. It can be used if you want to compare the object differently than in your IComparable implementation.

What is the meaning of Comparer?

comparer (plural comparers) One who, or that which, compares.

What is IEnumerable and IEnumerator in C#?

IEnumerable is an interface defining a single method GetEnumerator() that returns an IEnumerator interface. This works for readonly access to a collection that implements that IEnumerable can be used with a foreach statement. IEnumerator has two methods MoveNext and Reset. It also has a property called Current.

What is the default equality Comparer C#?

Equals(T) for equality, otherwise it will use your Equals(object) method. This method defaults to reference equality as defined in the object class. Therefore if you are defining equality using either method, you should ensure you also override GetHashCode as well.

Who is a compere person?

a person whose job is to introduce performers in a television, radio, or stage show: He started his career as a TV compere.

What is an example of comparing?

An example of compare is noticing how much two sisters look alike. To be regarded as similar or equal. (intransitive) To be similar (often used in the negative). A sapling and a fully-grown oak tree do not compare.

What’s the difference between IEnumerable and IEnumerator?

An IEnumerator is a thing that can enumerate: it has the Current property and the MoveNext and Reset methods (which in . NET code you probably won’t call explicitly, though you could). An IEnumerable is a thing that can be enumerated…which simply means that it has a GetEnumerator method that returns an IEnumerator .

How does IEnumerator work?

IEnumerable is an interface defining a single method GetEnumerator() that returns an IEnumerator interface. This works for read-only access to a collection that implements that IEnumerable can be used with a foreach statement. IEnumerator has two methods, MoveNext and Reset . It also has a property called Current .

When should I use IEquatable?

The IEquatable(T) interface is used by generic collection objects such as Dictionary(TKey, TValue) , List(T) , and LinkedList(T) when testing for equality in such methods as Contains , IndexOf , LastIndexOf , and Remove .

Does INT implement IEquatable?

Just take the above example, int implements the IEquatable. Likewise, the other primitive types also implement IEquatable. Generally, IEquatable is very useful for the value types.

What is the default equality Comparer?

The Default property checks whether type T implements the System. IEquatable interface and, if so, returns an EqualityComparer that uses that implementation. Otherwise, it returns an EqualityComparer that uses the overrides of Object. Equals and Object.

Can we have 2 abstract methods in functional interface?

A functional interface is an interface that contains only one abstract method. They can have only one functionality to exhibit. From Java 8 onwards, lambda expressions can be used to represent the instance of a functional interface. A functional interface can have any number of default methods.

Why do we use Comparator?

Comparator can be used to compare instances of different classes. Comparable is implemented by the class which needs to define a natural ordering for its objects. For example, String implements Comparable.

What is the role of compere?

A compere is the person who introduces the people taking part in a radio or television show or a live show. The person who comperes a show introduces the people who take part in it.

What is a female compere?

a female compere. Collins English Dictionary. Copyright © HarperCollins Publishers. Word origin. French, literally: godmother, from com- + mère mother; see compere.