3. What if we do not override Equals method ? What is we do not override Hashcode method?

Question

Accepted Answer

Not overriding equals method can lead to incorrect comparison of objects. Not overriding hashCode method can lead to incorrect behavior in hash-based data structures.

If equals method is not overridden, the default implementation from Object class will be used which compares object references.
This can lead to incorrect comparison of objects where two different objects with same content are considered unequal.
If hashCode method is not overridden, the default implementation from Object class will be used which returns the memory address of the object.
This can lead to incorrect behavior in hash-based data structures like HashMap or HashSet where objects with same content may not be stored or retrieved correctly.

Accepted Answer

If you don't override the Equals method in a class, the default implementation from the Object class will be used. This default implementation simply checks whether two object references refer to the same object in memory. In other words, it uses reference equality to determine if two objects are equal.

This default implementation may not be appropriate for many classes, particularly if you want to compare objects based on their state or content rather than their memory address. Therefore, it's often necessary to override the Equals method to provide a more appropriate definition of equality for your class.

On the other hand, if you don't override the GetHashCode method in a class, the default implementation from the Object class will also be used. This default implementation simply returns a unique hash code value for each object based on its memory address.

This default implementation may also not be appropriate for many classes, particularly if you've overridden the Equals method to define a custom definition of equality. In such cases, you should also override the GetHashCode method to ensure that equal objects have equal hash codes.

3. What if we do not override Equals method ? What is we do not override Hashcode method?

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