Basic Generics questions

What are Generics?

• The System.Collections.Generics namespace contains the generics collections.
• Generics can be a method, class, structure, or an interface to which it acts upon
• Generics  can be refer to a method ,class, structure or an interface in a type – safe manner
• Generics provide the ability to create type-safe collections in .NET.
• Generics.Net is a well organized class which contains data structures, algorithms, design patterns and other utilities in generic form.
• Generics are used to make the code more reusable.
• Generics can act like any data type means there is no need to write any internal code.

What are Constraints in Generics?

• Constraints are represented in C# using the where keyword
• Constraints is something restriction the way doing that in generics
• There are 3 types of Constraints

1.       Constructor constraint

2.       Derivation constraint

3.       Reference / value type constraints

What are Generics and Casting?

• The C# compiler only lets you implicitly cast generic type parameters to Object, or to constraint-specified types
• The compiler explicitly cast generic type parameters to only an interface but not a class.

 How to use I Dispose of a Generic Type?

• Just pass value of generic type parameter to the using statement then compiler will allow you to specify any instance of generic type

 How to declare Generic Methods?

• Generic method is defined by specifying the type parameter after the method name but before the parameter list.
• Doe Example public string Add(T val1, T val2).

 What is use of Generic List?

• Generic List is an efficient method of storing a collection of variables
• Generic List is strongly typed and casting.
• Name space to declare generics is using System.Collections.Generic.

Difference between Generics and Array List?

• Array List is not type safe because it faces problems of boxing and UN boxing.
• List generics are type safe and do not require boxing and UN boxing situations.
• In terms of performance of application List generics is better than array list.
• Array List can save different type data types.
• List generics we can save only specific data type.
• Array List consumes lots of memory compare to list generics/