C# Questions

struct vs Class

• structs are value types that can contain data and functions
• structs are value types and do not require heap allocation.
• structs directly store their data in the struct, classes store a reference to a dynamically allocated object.
• structs are useful for small data structures
• structs can affect performance
• Constructors are invoked with the new operator, but that does not allocate memory on the heap
• A struct constructor simply returns the struct value itself (typically in a temporary location on the stack), and this value is then copied as necessary
• With classes, multiple variables may have a reference to the same object
• It is possible for operations on one variable to affect the object referenced by the other variable.
• With structs, the variables each have their own copy of the data, and it is not possible for operations on one to affect the other.
• structs do not support user-specified inheritance, and they implicitly inherit from type object

Public struct PointStruct {  public int x;  public int y;  public PointStruct(int x, int y)  {   this.x = x;   this.y = y;  } } static void Main(string[] args) {  PointStruct ps = new PointStruct();  ps.x = 10;  ps.y = 10;  Console.WriteLine(“Initial struct values are “ + ps.x +”, “+ ps.y);  ModifyStructPoint(ps);  Console.WriteLine(“After ModifyStructPoint, struct values are “ + ps.x +”, “+ ps.y); } void ModifyStructPoint(PointStruct newStruct) {  newStruct.x = 20;  newStruct.y = 20;  Console.WriteLine(“Inside ModifyStructPoint()”);  Console.WriteLine(“Modified values are “ + newStruct.x +”, “+ newStruct.y); } Initial struct values are 10,10 Inside ModifyStructPoint() Modified values are 20,20 After ModifyStructPoint, struct values are 10,10

class PointClass {  public int x;  public int y;  public PointClass(int x, int y)  {  this.x = x;  this.y = y;  } } static void Main(string[] args) {  PointClass pc = new PointClass(10,10);  Console.WriteLine(“Initial class values are “ + pc.x +”, “+ pc.y);  ModifyClassPoint(pc);  Console.WriteLine(“After ModifyClassPoint, class are “ + ps.x +”, “+ ps.y); } void ModifyClassPoint(PointStruct newPoint) {  newPoint.x = 20;  newPoint y = 20;  Console.WriteLine(“Inside ModifyClassPoint()”);  Console.WriteLine(“Modified values are “ + newPoint.x +”, “+ newPoint.y); } Initial class values are 10,10 Inside ModifyClassPoint() Modified values are 20,20 After ModifyClassPoint, struct values are 20,20