Difference between == and Equals() Method in C#

Question

Ravi Vishwakarma · Answer

In C#, both the ‘==’ operator and the Equals() method are used to compare, but they work for different purposes and behaviors based on the context.
== Operator:
Purpose: The '==' operator is used to compare the similarity of two objects or values.Behavior: For reference types, == checks if two references point to the same object in memory by default. However, this behavior can be overridden by implementing the == operator or Equals() method in a custom way.Usage: It's commonly used for comparing built-in datatype types like integers, and floats, or for comparing reference types where reference equality is significant.
Example -
int a = 5;
int b = 5;
Console.WriteLine(a == b); // Output: True
string str1 = "hello";
string str2 = "hello";
Console.WriteLine(str1 == str2); // Output: True (reference equality for strings is overridden)
Equals() Method:
Purpose: The Equals() method is used to compare the similarity of two objects.Behavior: By default, Equals() compares reference equality for reference types (like ==), but this behavior can be overridden by classes to provide custom comparison logic.Usage: It's often used for comparing objects where custom equality comparison is required, such as comparing the contents of two string objects.
Example -
string str1 = "hello";
string str2 = "hello";
Console.WriteLine(str1.Equals(str2)); // Output: True
object obj1 = new object();
object obj2 = new object();
Console.WriteLine(obj1.Equals(obj2)); // Output: False (reference equality)
Differences:
Usage: The == operator is used for comparing equality, while the
Equals() method is a virtual method provided by the System.Object and can be overridden for custom equality comparison.Behavior: == typically compares reference equality for reference types unless overridden, whereas Equals() can be customized to compare content equality.Overriding: While == cannot be overridden directly, Equals() can be overridden in classes to provide custom comparison logic.Null Handling: == handles null references differently based on the type, while Equals() can handle null references if properly implemented.
In summary, use == for comparing equality where reference equality is significant or for built-in types, and use
Equals() for comparing objects where custom equality comparison logic is needed, or when dealing with reference types where reference equality might not be sufficient.

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Difference between == and Equals() Method in C#

Ravi Vishwakarma

1 Answers

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