C# interview questions on Constructors and destructors
What is a constructor in C#?
Constructor is a class method that is executed when an object of a class is created. Constructor has the same name as the class, and usually used to initialize the data members of the new object.
In C#, What will happen if you do not explicitly provide a constructor for a class?
If you do not provide a constructor explicitly for your class, C# will create one by default that instantiates the object and sets all the member variables to their default values.
Structs are not reference types. Can structs have constructors?
Yes, even though Structs are not reference types, structs can have constructors.
We cannot create instances of static classes. Can we have constructors for static classes?
Yes, static classes can also have constructors.
Can a class or a struct have multiple constructors?
Yes, a class or a struct can have multiple constructors. Constructors in csharp can be overloaded.
Can a child class call the constructor of a base class?
Yes,
Can you mark static constructor with access modifiers?
No, we cannot use access modifiers on static constructor.
Can you have parameters for static constructors?
No, static constructors cannot have parameters.
What happens if a static constructor throws an exception?
If a static constructor throws an exception, the runtime will not invoke it a second time, and the type will remain uninitialized for the lifetime of the application domain in which your program is running.
Give 2 scenarios where static constructors can be used?
1. A typical use of static constructors is when the class is using a log file and the constructor is used to write entries to this file.
2. Static constructors are also useful when creating wrapper classes for unmanaged code, when the constructor can call the LoadLibrary method.
Does C# provide copy constructor?
No, C# does not provide copy constructor.
