What is the difference between IComparable and IComparer?
IComparable when defined for T lets you compare the current instance with another instance of same type. IComparer is used to compare any two instances of T , typically outside the scope of the instances of T .
What is IComparable?
The IComparable interface defines a generalized type-specific comparison method that a value type or class implements to order or sort its instances. The IComparable is implemented by types whose values can be ordered or sorted. The interface requires the CompareTo method to be implemented.
Why IComparable is used in C#?
Use the IComparable Interface in C# to sort elements. It is also used to compare the current instance with another object of same type. It provides you with a method of comparing two objects of a particular type. Remember, while implementing the IComparable interface, CompareTo() method should also be implemented.
What is IComparer in C#?
IComparer interface provides Compare method that Compares two objects and returns a value indicating whether one is less than, equal to, or greater than the other. A class that implements the IComparer interface must provide a Compare method that compares two objects.
Can we compare two objects in C#?
The most common way to compare objects in C# is to use the == operator. For predefined value types, the equality operator (==) returns true if the values of its operands are equal, false otherwise. For reference types other than string, == returns true if its two operands refer to the same object.
How custom sort is implemented in C#?
For sorting any custom type the class must implement the System. IComparable interface which allow the object to be sorted based on some specified key. // IComparable implementation….Sorting Collection of Custom Type using Generic.
| CompareTo() | Return Value Meaning |
|---|---|
| Zero | This instance is equal to the specified object. |
Does string implement IComparable?
All numeric types (such as Int32 and Double) implement IComparable, as do String, Char, and DateTime.
What is where in C#?
The where clause is used in a query expression to specify which elements from the data source will be returned in the query expression. It applies a Boolean condition (predicate) to each source element (referenced by the range variable) and returns those for which the specified condition is true.
What are generics in c# net?
Generic is a class which allows the user to define classes and methods with the placeholder. Generics were added to version 2.0 of the C# language. The basic idea behind using Generic is to allow type (Integer, String, … etc and user-defined types) to be a parameter to methods, classes, and interfaces.
Can I use == to compare strings in C#?
You can check the equality of strings using two ways: Using == operator. Using Equals() method….== vs Equals.
| == | Equals() |
|---|---|
| Compares the content of strings. | Compares the content of strings. |
How do you sort a class in C#?
C# List Sort method
- Sort(Comparison) – Sorts the elements in the entire List using the specified Comparison.
- Sort(Int32, Int32, IComparer) – Sorts the elements in a range of elements in List using the specified comparer.
- Sort() – Sorts the elements in the entire List using the default comparer.
What is the difference between IComparable and IComparer interface in C#?
Difference between IComparable and IComparer Interface in C# 1 IComparable Interface in C#. Use the IComparable Interface in C# to sort elements. 2 IComparer interface in C#. The IComparer interface is used to sort elements that compare two objects and provides additional comparison method. 3 Example. Now return an instance of IComparer object.
How do you compare two objects in IComparer?
IComparer interface provides Compare method that Compares two objects and returns a value indicating whether one is less than, equal to, or greater than the other. A class that implements the IComparer interface must provide a Compare method that compares two objects.
How to sort on different properties with compareTo method from IComparable?
The CompareTo method from IComparable interface can sort on only one field at a time, so sorting on different properties with it is not possible. IComparer interface provides Compare method that Compares two objects and returns a value indicating whether one is less than, equal to, or greater than the other.
What is contravariance in IComparer?
In .NET 4, IComparer has been changed to IComparer , which means that objects of type T are used only as input parameters. Therefore, an object implementing this interface can be assigned to interfaces of a more derived type. This is called contravariance.