Introduction to CS Basis Concepts.

1. Array:

Array concept is demostrated in the file ArrayDemo.cs This files demos the below concept:

• Declaring Arrays
• Adding item to arrays
• getting the item count from Arrays

Here only few of the Array mmethods are shown but you can play around with that since intelisence will give all the details. Note that to use any of tha static method of Array class use Array. and intelisense will poulate all the static methods. And to use any of the instance methods use ArrayInstanceVariable., here ArrayInstanceVariable is tha array variable you define.

2. List:

Lists concept is demostrated in the file List.cs This files demos the below concept:

• Declating List
• Adding to list
• getting item count from list

3. Dictionary:

Dictionary concept is demostrated in the file DictionaryDemo.cs This file demonstrates the use of Dictionary. Dictionaries are datatype in C# that can be used to keep key-value pair.

This file demonstrates the below concepts:

• Initializing a dictionary.
• Additng item to dictionary
• Get Item from dictionary
• Check if an item exists in a dictionary
• Return item from dictionay only if it exists.
• Loop a dictionary on Key
• Loop a dictionary on Value
• Loop dictionary on elements

4. Enums:

Emums concept is demostrated in the file Emums.cs. Enums are data types that is used to represent a numebric value. The vaue starts from 0 by default. But it can be configured.

5. Break and Continue:

Break and Continue concept is demostrated in the file BreakContinue.cs This file demonstrates below concepts

• Break
• Continue

6. Constructors:

Constructors concept is demostrated in the file Constructor.cs. This files demos the below concept:

• Constructore
• Parameterized constructor
• "this" keyword

7. Exceptions:

Exception concept is demostrated in the file ExceptionDemo.cs. This file demos the below concepts

• exception
• handling exception
• throwing exception
• finally block

8. Control Flow And Loop:

Control Flow & Loop concept is demostrated in the file FlowAndLoop.cs. This files demos the below concept:

• If control flow
• For loop
• For each loop
• While loop
• Do while loop

9. ForEach Loop:

ForEach loop concept is demostrated in the file ForEach.cs. This files demos the below concept:

• foreach loop

This is also explained with other loops in FlowAndLoop.cs file. Please do refer to that as well.

10. Formatting Specifier:

Formatting Specifier concept is demostrated in the file FormattingSpecifier.cs. This files demos the below concept:

• format specifiers

11. Lambda Methods:

Lambda Method concept is demostrated in the file LambdaMethod.cs. This class demons the Lamda Methods (also called as expression bodied methods) If your method code is just a line and is used to return a value you can use lamda methods. The syntax is simple and the operator is =>

12. Min Max Static:

Min, Max and Static concept is demostrated in the file MinMaxStatic.cs. This files demos the below concept:

• Double.MinValue
• Double.MaxValue
• Math.Min
• Math.Max
• Static : This is just discussed and not demoed.

Static Methods and methods that are not associated with object instance. If a method is static you cannot call it with class object. Also all the members of a static methids must be static. for example see the main method.

Also you can see below example

Class DemoStatic
{
   public DemoStatic()
   {
       number = new List<Double> {1.1, 1.2., 3.3, 4.4};
   }

    static public DemoStatic(double newNumber)
    {

      number.Add(newNumber); // number must be static since this is a static method

    }

    static private List<double> number; // note that this is static member
}

13. Nullable Type:

Nullable Type concept is demostrated in the file NullableTypeDemo.cs. Nullable type is a value type that allows defination of a value or null. This class helps us to demo the below concepts

• Nullable Types The syntax is simple and the operator is =>

14. Null Checking:

Null Checking concept is demostrated in the file NullCheckingDemo.cs. C# supports ?. operator to check null values. This class demos the use of ?. operator for null checking "?. is evaluated as "if null then null, if not then dot" That means if left side or the operator is null then the expression is null and the expression will not be evaluated further. If not then . will be used and the expression will be evaluated further. *

NullableTypeDemo.cs is referenced for this demo.

15. Object Initializer:

Object Initializer concept is demostrated in the file ObjectInitializerDemo.cs and SuperHero.cs. This class is used to demo object initializers for C#. NOTE that this file will hav 3 classes for the demo purpose. There are three ways how object can be initialized. Default Constructor, Parameterized Constructor and Object Initializers. CSBasic.cs and Unit Test will demonstate the object initilization

16. Method Over Loading:

Method Over Loading concept is demostrated in the file OverLoading.cs. This file demonstrates the concept of

• method overloading

17. String Interpolation:

String Interpolation concept is demostrated in the file StringInterpolation.cs. This files demos the below concept:

• string interpolation

18. Properties:

Properties concept is demostrated in the file Properties.cs. This files demos the below concept:

• Class Properties (getters and setters)
• Autoimplemented Properties
• Calculated value properties
• Expression Value properties

19. Reading From Console:

Reading From Console concept is demostrated in the file ReadFromConsole.cs. This short method demonstrates how we can read data from console. This file demonstrates the below concept:

• reading data from console.

20.ReadOnly And Constant:

ReadOnly And Constant concept is demostrated in the file ReadOnlyAndConstant.cs. This files demos the below concept:

• ReadOnly Fields
• Constant Fields

21.Reading and Writing to File:

Reading and Writing to File concept is demostrated in the file ReadWriteFile.cs. This file demonstrates the use of iDisposable. The concept simply tells how C# handles if the file or stream is not closed before the program exits. This file demonstrates the use of below statement

• using

22.Inheritence and Abstract class:

Inheritancce concept is demostrated in the file Company.cs and CompanyIT.cs. Company class is meant to serve as the base class for the demo or inheritence. NOTE that C# support only single inheritence.

CompanyIT class is used to demonstrate the concept of Inheritence. CompanyIT inherits the class Company.

Please notice that the methods in Company class is re-used, abstract classes are impemented and virtual methods are over-riddedn.

Below cocepts will be demoed using Company.cs and CompanyIT.cs:

• Inheritence
• Abstract class
• Virtual Methods
• Method over-riding

23.Interface:

Interface concept is demostrated in the file ICompany.cs, CompanyHospitality.cs and CompanyShipping.cs. CompanyHospitality and CompanyShipping class is used to demonstrate the concept of Interface. Thiese classes implements the interface ICompany.

You can notice how this is different from an Abstract class. Also please notice that all the methods and getters and setters are declared in the interface. All the implementation is done here.

ICompany class is meant to serve as the interface class for the demo or ICompany NOTE that C# support only single inheritence but more than 1 inerface can be implemented by the class. Also it is a standart practice to start the interface name with "I", ICompany in this case.

Below cocepts will be demoed using ICompany.cs, CompanyHospitality.cs and CompanyShipping.cs

• Interface
• more than once class can implememt the same interface
• a class can implement more than one interface as well

24.Generic Interface:

Generic Interface concept is demostrated in the file AccessoriesArray.cs, AccessoriesList.cs and IAccessories.cs. AccessoriesArray and AccessoriesList class is used to demonstrate Generic Interface. This implements IAccessories Also please look AccessoriesList. IAccessories class is a generic iterface. The idea is to demo how this same interface can be used work on diffrent kind of data. Please note that here only one generic is used. But more than one generic can also be used in similar faishon.

AccessoriesList and AccessoriesArray class implements this interface.

25.Generic Method:

Generic Method concept is demostrated in the file TMethod.cs. This file demos how we can create generic method that cam accept variable of any data type. Follow through the comments and you will see what all is required to have a generic method. NOTE that using 'T' is a common practice to represent generic parameters. You can also use other name like 'TMessage', 'TValue' etc to be more descriptive, especially when there are more than 1 generic parameter.

26.Generic Class:

Generic Class concept is demostrated in the file TClassOne.cs and TClassMany.cs. This file demos how we can create generic class with single variable that is generic. Follow through the comments and you will see what all is required to have a generic class. NOTE that using 'T' is a common practice to represent generic parameters. You can also use other name like 'TMessage', 'TValue' etc to be more descriptive, especially when there are more than 1 generic parameter.

27. Generic Constraints

Generic Constraints concept is demostrated in the file GenericConstraints.cs. This file demos the generic constraints. Here is a writeup on the supported constraints where T : struct <= Value Type where T : class <= Reference Type where T : new() <= Type has a parameterless constructor where T : vendor() <= Be or derive from a class (for example class Vendor) where T : IVendor <= Be or implement the IVendor interface