What is the difference between IComparer and IComparable in C

IComparable<T> when defined for T lets you compare the current instance with another instance of same type. … IComparer<T> 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.

What does CompareTo return in C#?

CompareTo() Method is used to compare the current instance to a specified object or to another Single instance and returns an integer which shows whether the value of the current instance is greater than, equal to, or less than the value of the specified object or the other Single instance.

What is use of IComparable 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 the difference between comparable and IComparer?

IComparable has a method named as CompareTo & has only 1 parameter. Because it compares the current object with the next object which is coming as a parameter. Hence current object CompareTo next object. But IComparer has 2 parameters because we are going to pass both of the objects as arguments.

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.

Does string implement IComparable C#?

This current instance follows the object specified by the CompareTo method in the sort order. All numeric types (such as Int32 and Double) implement IComparable, as do String, Char, and DateTime. Custom types should also provide their own implementation of IComparable to enable object instances to be ordered or sorted.

What is IEqualityComparer C#?

IEqualityComparer is a very important interface for comparer tasks in the LinQ world. The next extended methods have an overload with this parameter type: Contains, Distinct, Except, Intersect, GrouBy, GroupJoin, Join, SecuenceEqual, ToDictionary, ToLookUp and Union.

What is Interface class in C#?

Interface in C# is a blueprint of a class. It is like abstract class because all the methods which are declared inside the interface are abstract methods. It cannot have method body and cannot be instantiated. It is used to achieve multiple inheritance which can’t be achieved by class.

How do you equal a string in C#?

==Equals()Compares the content of strings.Compares the content of strings.

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What is the return type of compareTo () method?

The compareTo() method compares two strings lexicographically. … The method returns 0 if the string is equal to the other string. A value less than 0 is returned if the string is less than the other string (less characters) and a value greater than 0 if the string is greater than the other string (more characters).

What is returned from both the Compare () and compareTo () methods?

The Java String compareTo() method is used for comparing two strings lexicographically. Each character of both the strings is converted into a Unicode value for comparison. If both the strings are equal then this method returns 0 else it returns positive or negative value.

Can I use == to compare strings in C #?

You can’t compare strings in C with ==, because the C compiler does not really have a clue about strings beyond a string-literal. In C because, in most contexts, an array “decays into a pointer to its first element”. Because there is no such thing as a C string.

What is equal method?

The equals() method compares two strings, and returns true if the strings are equal, and false if not. Tip: Use the compareTo() method to compare two strings lexicographically.

Are objects equal C#?

The static Equals(Object, Object) method indicates whether two objects, objA and objB , are equal. It also enables you to test objects whose value is null for equality. It compares objA and objB for equality as follows: It determines whether the two objects represent the same object reference.

What is boxing and unboxing in C#?

Boxing is the process of converting a value type to the type object or to any interface type implemented by this value type. … Object instance and stores it on the managed heap. Unboxing extracts the value type from the object. Boxing is implicit; unboxing is explicit.

How many types of interfaces are there in C#?

Some of the interface types in C# include. IEnumerable − Base interface for all generic collections. IList − A generic interface implemented by the arrays and the list type. IDictionary − A dictionary collection.

Can an interface extend another interface C#?

C# allows the user to inherit one interface into another interface. When a class implements the inherited interface then it must provide the implementation of all the members that are defined within the interface inheritance chain.

What collection would use an IEqualityComparer to enforce uniqueness?

The Distinct extension method returns a new collection of unique elements from the given collection. The Distinct extension method doesn’t compare values of complex type objects. You need to implement IEqualityComparer<T> interface in order to compare the values of complex types.

Can we compare two strings in C?

We compare the strings by using the strcmp() function, i.e., strcmp(str1,str2). This function will compare both the strings str1 and str2. If the function returns 0 value means that both the strings are same, otherwise the strings are not equal.

What is string in C# with example?

In C#, a string is a series of characters that is used to represent text. It can be a character, a word or a long passage surrounded with the double quotes “. The following are string literals. Example: String Literals. “S” “String” “This is a string.”

How do you compare strings?

The compareTo() method compares the Unicode value of each character in the two strings you are comparing. compareTo() returns 0 if the string is equal to the other string, less than 0 if the string has fewer characters than the other string, and greater than 0 if the string has more characters than the other string.

What compare returns Java?

The compare() method in Java compares two class specific objects (x, y) given as parameters. It returns the value: 0: if (x==y) -1: if (x < y)

How can I compare two BigDecimal values?

compareTo(BigDecimal bg) method checks for equality of this BigDecimal and BigDecimal object bg passed as parameter. The method considers two equal BigDecimal objects even if they are equal in value irrespective of the scale.

How do you compare two strings in if condition?

Examples. The right way of comparing String in Java is to either use equals(), equalsIgnoreCase(), or compareTo() method. You should use equals() method to check if two String contains exactly same characters in same order. It returns true if two String are equal or false if unequal.

How do you check for lexicographical strings?

1. if (string1 > string2) it returns a positive value.
2. if both the strings are equal lexicographically. i.e.(string1 == string2) it returns 0.
3. if (string1 < string2) it returns a negative value.

How does compareTo work for integers?

compareTo() method compares two Integer objects numerically. This method returns the value 0 if this Integer is equal to the argument Integer, a value less than 0 if this Integer is numerically less than the argument Integer and a value greater than 0 if this Integer is numerically greater than the argument Integer.

What is Java comparable interface?

The Java Comparable interface, java. lang. Comparable , represents an object which can be compared to other objects. For instance, numbers can be compared, strings can be compared using alphabetical comparison etc. Several of the built-in classes in Java implements the Java Comparable interface.

What does == mean in C?

== is an Equal To Operator in C and C++ only, It is Binary Operator which operates on two operands. == compares value of left and side expressions, return 1 if they are equal other will it will return 0.

What is length of string in C?

A string in C language is an array of characters that is terminated with a null character (\0). The string length is the number of characters in a string. … In the example shown above, the length of the string str is 6.

Is C# string comparison case-sensitive?

Generally, in c# the string Equals() method will perform case-sensitive string comparison. If we want to perform case insensitive string comparison, we need to use the OrdinalIgnoreCase property and the Equals method.