Dot Net interview questions

Warm Up Questions

Is “string” value or reference type?

It is a reference type. string is an alias of String

Is int[] counter is a value or reference type?
Arrays are intrincically derived from System.Array.

Is Nullable types are value or reference type?
All nullable types are of Type System.Nullable struct

Is it possibe to define a variable of type
Nullable> number;
int ?? number;

Rapid Fire Round

Why Generics?
Allows to design class or method that defer the specification of one or more types until used by client.

Avoids Boxing and Unboxing (Performance)

Avoids Runtime exceptions (type safety)

Better programming (Code reuse)

What type would return if “is” operator is used on
List counterList = null;

Underlying type will be returned not the Nullable type.

The very Basics (Not Visual Basic)

Can delegates added to invocation list be changed?
NO

Does delegates are invoked once for each time they appear in the invocation list?
Yes it does.

Can multiple catch blocks be executed?
No.

Can return statement in try block make finally block called?
Yes.