C# Similarities and differences between Struct and Class

Similarities

In C#, both struct and class are used to define custom data types, and they share several similarities:

• Members: Both structs and classes can have members like fields, properties, methods, and events.
• Object-Oriented: Both structs and classes are object-oriented constructs, allowing you to model and encapsulate data and behavior in your code.
• Constructors: You can define constructors for both structs and classes to initialize their objects.
• Access Modifiers: You can use access modifiers like public, private, protected, and internal to control the visibility of members in both structs and classes.
• Inheritance: Both structs and classes support inheritance, allowing you to create derived types that inherit members from a base type.
• Properties: You can define properties in both structs and classes to encapsulate the access to their fields.

Differences

However, there are some key differences between struct and class in C#:

• Value vs. Reference Types: structs are value types, which means they are copied when passed as arguments or assigned to new variables. classes are reference types, and only references to objects are passed around, not the actual object data.
• Nullability: Variables of a struct type cannot be assigned a null value, whereas variables of a class type can be assigned null.
• Memory Allocation: structs are typically allocated on the stack, while classes are allocated on the heap. This can have performance implications, as stack allocation is generally faster.
• Default Constructor: structs have an implicit parameterless constructor, which initializes all their fields to their default values. classes do not have an implicit parameterless constructor; you must define one explicitly if needed.
• Mutability: structs are usually considered immutable, and changing the value of a field requires creating a new struct. classes can be mutable, and you can modify their properties and fields directly.
• Boxing and Unboxing: structs do not require boxing and unboxing when used as method arguments or stored in collections, which can improve performance in certain scenarios.

In summary, both structs and classes in C# share similarities in terms of members, object-oriented features, and access modifiers. However, they differ in terms of value/reference semantics, memory allocation, nullability, default constructors, mutability, and boxing/unboxing behavior. Choosing between struct and class depends on the specific requirements and characteristics of your data type and its usage.