C# Presentation

By Santosh Tawde

Introduction

C#, pronounced “C Sharp,” is one of the new languages in the .NET framework being implemented by Microsoft. All .NET languages compile to a common byte code (MSIL) making their integration into programs written in different languages easier.

C# Presentation, Spring 2003

History

• C
• C++
• Developed by Anders Hejlsberg
• Turbo Pascal
• Delphi
• Visual J++
• Released in 2001-2002

C# Presentation, Spring 2003

Previous Problems

• Memory Leaks
• Illegal Pointer References
• Overly Complex Multiple-Inheritance
• Static Linking

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C# Presentation, Spring 2003

Resolutions

• Garbage Collection
• Threw out pointers
• Single inheritance with Interfaces
• Dynamic Linking
• Done 5 years ago in Java

C# Presentation, Spring 2003

What is C#

• Contrary to popular belief, C# is not simply a clone of or replacement for Java
• According to Anders Hejlsberg, Microsoft’s Chief Architect, C# is a derivation of C++, C, Java, Modula 2, and Smalltalk

C# Presentation, Spring 2003

What is C#

• C# combines the best features of these languages and eradicates some of their weaknesses

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C# Presentation, Spring 2003

Why Choose C#?

• C# was designed from scratch with the .net framework in mind
• C# combines the power of C and C++ with the productivity of Visual Basic
• With its familiar syntax the transition for Java and C++ programmers will be an easy one

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C# Presentation, Spring 2003

Why Choose C#?

C# is in sync with current web standards and is easily integrated with existing applications.

In today’s society where internet programming is inevitable having a language that already supports this makes the job of the developer easier.

C# Presentation, Spring 2003

Example of Code

The code looks a lot like Java

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public class Example

{

public static void Main(string[] args)

{

foreach (string s in args)

{

System.Console.WriteLine(s);

}

}

}

​

C# Presentation, Spring 2003

Features

• OOP

C# Presentation, Spring 2003

OOP

C# is object oriented. Every class is a subclass of an object. Everything is an object, yes even primitives. This makes generic programming easier.

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Example:

int n = 3;

string s = n.ToString();

C# Presentation, Spring 2003

Features

• OOP
• Enumerators

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C# Presentation, Spring 2003

Enumerators

Enumerators are a borrowed idea from C/C++. This is a data type consisting of a set of of named integers.

Example:

enum Weekday {Mon, Tues, Wed, Thu,

Fri, Sat, Sun};

C# Presentation, Spring 2003

Features

• OOP
• Enumerators
• Operator Overloading

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C# Presentation, Spring 2003

Operator Overloading

Operator Overloading is yet another idea borrowed from c++. This makes polymorphism easier with custom data types.

Example:

Currency a, b, c;

c = a + b;

C# Presentation, Spring 2003

Features

• OOP
• Enumerators
• Operator Overloading
• Windows API Invocation

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C# Presentation, Spring 2003

Windows API Invocation

C# was built with Windows in mind. It was created to allow programmers to create Windows application easily through a wraparound API. Some other technologies supported are COM, COM+.

C# Presentation, Spring 2003

Features

• OOP
• Enumerators
• Operator Overloading
• Windows API Invocation
• Structured Error Handling

C# Presentation, Spring 2003

Structured Error Handling

C# introduces new error handling techniques.

Try-catch blocks are used but with more functionality.

To throw an object, it has to be a subclass of System.Exception.

C# Presentation, Spring 2003

Try-Catch

C# Presentation, Spring 2003

try-catch blocks could be any of the following;

• try{ } catch(SomeException){ }
• try{ } catch(){ } //catches any kind of exception
• try{ } catch(){ } finally{ } //finally is always executed
• try{ } finally{ } //finally is always executed

Features

• OOP
• Enumerators
• Operator Overloading
• Windows API Invocation
• Structured Error Handling
• Delegates

C# Presentation, Spring 2003

Delegates

Delegates provide a template for a single method.

Example:

• public delegate int ArithOp(int a, int b);
• …
• public int DoOp(ArithOp ar)
• { return ar(a, b); }

C# Presentation, Spring 2003

Features

• OOP
• Enumerators
• Operator Overloading
• Windows API Invocation
• Structured Error Handling
• Delegates
• Namespaces

C# Presentation, Spring 2003

Namespace

Namespace is a method of organizing similar files together. This is similar in some way to the java package idea. Every program is either explicitly within a namespace or in by default.

Example:

• namespace Project{ public class P1{} }
• public class P2{}

C# Presentation, Spring 2003

Namespace

C# Presentation, Spring 2003

To use a namespace, you just simply import by using the keyword using.

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Example:

using system;

public class P1{}

Future of C#

With C#’s flexibility and support for many languages through the .NET architecture it will definitely become a widely used language in all aspects of programming.

C# Presentation, Spring 2003

Bibliography

• C# programming, Harvey, Robinson, Templeman, Watson
• http://www.funducode.com/csharp/basics/basics1.htm
• http://www.simonrobinson.com/DotNET/Articles/Languages/IntroCSh.aspx
• http://windows.oreilly.com/news/hejlsberg_0800.html
• http://msdn.microsoft.com/msdnmag/issues/0900/csharp/default.aspx

C# Presentation, Spring 2003