Mr. G.C.Deshpande

Lecturer, CSE@KLS.GIT

Topic Level ObjectivesTopic Level ObjectivesTo examine the core constructs of the C# programming language. To familiarize basic class construction techniques, the distinction between value types and reference types, boxing and unboxing, and the role of favorite base class, System.Object. To exemplify various commonplace programming constructs in .NET platform, such as flow control, enumerations, arrays, structures, classes and string processing.

Intended Learning OutcomesIntended Learning Outcomes1. Illustrate the concept of boxing and unboxing [L 5].2. Explain the role of nullable data types [L 2].3. Create custom namespaces [L 5].4. Investigate various aspects of Common Language Runtime [L 4].5. Explain the basic structure of C# program [L 2].6. Discuss the variations of Main() method [L 2].7. Explain the role of System.Object [L 2].8. Discuss various parameter passing conventions, value types and reference types [L 2].9. Define classes and objects, also application object [L 1].10. Explain the role of constructors [L 2].11. Discuss Basic input and output methods of console class [L 2].12. Differentiate between constructors and static constructors [L 4].13. Explain various Iteration constructs, decision constructs and relational operators [L 2].14. Compare iteration constructs of C# with the iteration constructs of other languages [L 6].

The Anatomy of Simple C# The Anatomy of Simple C# ProgramProgram

The Anatomy of Simple C# The Anatomy of Simple C# ProgramProgram

The Anatomy of Simple C# The Anatomy of Simple C# ProgramProgram

Variations on the Main() Variations on the Main() MethodMethod

Processing Command-Line Processing Command-Line ArgumentsArguments

Processing Command-Line Processing Command-Line ArgumentsArguments

Processing Command-Line Processing Command-Line ArgumentsArguments

C# Iteration ConstructsC# Iteration Constructs

for loop foreach loop while loop do….while loop

The for loopThe for loop

Iteration over block of code for fixed number of times

The foreach loopThe foreach loop

Iteration over all items within an array without checking the upper limit

The while loopThe while loop

Iteration over block of code until some terminating condition

The do….while loopThe do….while loop

Iteration over block of code for undetermined number of times

Decision ConstructsDecision Constructs

The if/else statement The switch statement

The if/else statementThe if/else statement

The switch statement The switch statement

The switch statementThe switch statement

EnumerationsEnumerations

EnumsEnums

Enums in switch statementEnums in switch statement

Enums in switch statementEnums in switch statement

Structures Structures

Structures Structures

(methods, properties)

Structures – creating variablesStructures – creating variables

Structs with custom constructorStructs with custom constructor

Strings in C#Strings in C#

Strings in C#Strings in C#

Strings in C#Strings in C#

Strings in C#Strings in C#

Strings in C#Strings in C#

Verbatim StringsVerbatim Strings

Strings in C#Strings in C#

Strings are immutableStrings are immutable

Arrays in C#Arrays in C# An array is a set of data items, accessed using a numerical index

An array is a set of contiguous data points of the same type

Arrays in C#Arrays in C#

C# Array Initialization SyntaxC# Array Initialization Syntax

Implicitly typed local arraysImplicitly typed local arrays

Array of objectsArray of objects

Multidimensional Arrays Multidimensional Arrays [ Rectangular ][ Rectangular ]Declarationint[,] myArray = new int[4,2];

int[,,] myArray = new int [4,2,3];

Initializationint[,] myArray = new int[,] {{1,2}, {3,4}, {5,6}, {7,8}};int[,] myArray = {{1,2}, {3,4}, {5,6}, {7,8}};

int[,] myArray;myArray = new int[,] {{1,2}, {3,4}, {5,6}, {7,8}}; // OKmyArray = {{1,2}, {3,4}, {5,6}, {7,8}}; // Error

Multidimensional Arrays Multidimensional Arrays [ Rectangular ][ Rectangular ]

Multidimensional Arrays Multidimensional Arrays [ Jagged ][ Jagged ] A jagged array is an array whose elements are arrays. The elements of a jagged array can be of different dimensions and

sizes. A jagged array is sometimes called an "array-of-arrays.“ 

Declaration

int[][] myJaggedArray = new int[3][];

Initialization

myJaggedArray[0] = new int[5];

myJaggedArray[1] = new int[4];

myJaggedArray[2] = new int[2];

myJaggedArray[0] = new int[] {1,3,5,7,9}; myJaggedArray[1] = new int[] {0,2,4,6}; myJaggedArray[2] = new int[] {11,22};

Multidimensional Arrays Multidimensional Arrays [ Jagged ][ Jagged ]Initialization

int[][] myJaggedArray = new int [][] { new int[] {1,3,5,7,9}, new int[] {0,2,4,6}, new int[] {11,22}

};

int[][] myJaggedArray = { new int[] {1,3,5,7,9}, new int[] {0,2,4,6}, new int[] {11,22}

};

Multidimensional Arrays Multidimensional Arrays [ Jagged ][ Jagged ]Initialization

// Assign 33 to the second element of the first array: myJaggedArray[0][1] = 33;

// Assign 44 to the second element of the third array: myJaggedArray[2][1] = 44;

Mixing of arraysint[][,] myJaggedArray = new int [3][,] {

new int[,] { {1,3}, {5,7} },new int[,] { {0,2}, {4,6}, {8,10} }, new int[,] { {11,22}, {99,88}, {0,9} }

};

Multidimensional Arrays Multidimensional Arrays [ Jagged ][ Jagged ]

The System.Array Base ClassThe System.Array Base Class

Methods and Parameter Methods and Parameter ModifiersModifiers

Methods and Parameter Methods and Parameter ModifiersModifiers

Default Parameter Passing Default Parameter Passing BehaviorBehavior

The out ModifierThe out Modifier

The out ModifierThe out Modifier

The ref ModifierThe ref Modifier

The params ModifierThe params Modifier

The params ModifierThe params Modifier

Defining Optional ParametersDefining Optional Parameters

Defining Optional ParametersDefining Optional Parameters

Value Types and Reference Value Types and Reference TypesTypes

Value Types and Reference Value Types and Reference TypesTypes

BoxingBoxingConversion from value type to reference type

int m=100;

object om=m; //creates a box to hold m

int m=100;

object om=(object)m; //c-style casting

int m=10;

object om=m;

m=20;

console.writeline(m); //m=20

console.writeline(om); //om=10

UnboxingUnboxingConversion from reference type to value type

int m=10;

object om=m; //box m

int n=(int)om; //unbox om

int m=500;

object om=m

byte n=(byte)om; // run-time error

Remember: We can only unbox a variable that has previously been boxed

ReferencesReferences

1] Andrew Troelsen, Pro C# with .NET 3.0, Special Edition,

Dream tech Press, India, 2007.

2] E. Balagurusamy, Programming in C#, 5th Reprint, Tata McGraw Hill,

2004 (For Programming Examples).

3] Tom Archer, Inside C#, WP Publishers, 2001.

4] Herbert Schildt, C#: The Complete Reference, TMH, 2004. 

5] Yashavant Kanetkar, C#.NET fundas, First Edition, BPB Publications,

2002

 

Contact MeContact Me

Email: gcdeshpande@git.edu

gcdeshpande@hotmail.com

Blog: gcdeshpande.spaces.live.com

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