C# Origins and Development PDF

ORIGINS AND C# 3.0 (2007) Key innovations: DEVELOPMENT OF C# LINQ (Language Integrated Query): Allowed C# Creation and Microsoft’s Role querying data (from collections, databases, (...

ORIGINS AND C# 3.0 (2007) Key innovations: DEVELOPMENT OF C# LINQ (Language Integrated Query): Allowed C# Creation and Microsoft’s Role querying data (from collections, databases, (2000) XML, etc.) using C# syntax. C# was developed by Microsoft as part of Lambda Expressions: Enabled more its.NET initiative, led by Anders Hejlsberg. concise and functional programming The goal was to create a modern, patterns. objectoriented programming language that Extension Methods: Allowed adding would be simple, efficient, and secure, methods to existing types without modifying designed for the.NET Framework. them. It was introduced to address some limitations in languages like C++ and Java, providing a powerful yet user-friendly tool for C# 4.0 (2010) developers. Focused on improving interoperability with dynamic programming languages: Initial Release - C# 1.0 (2002) Dynamic Type: Enabled dynamic typing for easier interaction with COM objects, Released with Visual Studio.NET, C# 1.0 dynamic languages like Python, or focused on core object-oriented principles, JavaScript. garbage collection, exception handling, and a familiar C/C++ style syntax. Named and Optional Parameters: Simplified function calls with default values. The language was tightly integrated with the.NET Framework, leveraging the C# 5.0 (2012) Common Language Runtime (CLR) for cross- Major improvement: language compatibility. Asynchronous Programming (async/await): Revolutionized how developers wrote KEY EVOLUTION asynchronous and concurrent code, making it more readable and maintainable. MILESTONES: C# 6.0 (2015) C# 2.0 (2005) Introduced significant Focused on improving syntax: language enhancements: Auto-Property Initializers: Simplified Generics: Allowed for creating type-safe property declarations. collections and methods. Null-Conditional Operators (?.): Reduced Anonymous Methods: Helped developers the risk of NullReferenceException by write more flexible and concise code. providing concise syntax for null checks. String Interpolation: Simplified string Iterators: Simplified the process of formatting by embedding expressions within enumerating through collections. string literals. C# 7.0 and 7.1 (2017) Asynchronous Streams (Async Iterators): Enhanced async programming, making it Enhancements to make the language more easier to work with data streams. expressive: Switch Expressions: Further modernized Tuples: Introduced lightweight data pattern matching syntax. structures for returning multiple values. Pattern Matching: Allowed more expressive and functional code by matching patterns in C# 9.0 (2020) switch statements and other contexts. Focused on immutability and simplifying Local Functions: Enabled defining code: functions inside other functions for Records: Introduced for creating encapsulation. immutable, lightweight data objects. Pattern matching in C# allows you to test Init-Only Properties: Allowed setting whether a value fits a certain pattern and properties only during initialization, extract data from that value. It simplifies improving immutability. conditional logic by enabling type checks, value checks, and decomposing data C# 10.0 (2021) structures in a more concise and readable manner. Aimed at reducing boilerplate code: Global Usings: Simplified managing namespaces by defining common using directives globally across files. File-Scoped Namespaces: Allowed for more compact namespace declarations. Record Structs: Extended records to support value types, offering benefits of records for structs. C# 11.0 (2022) Recent improvements include: Raw String Literals: Made working with multi-line and special-character strings easier without requiring extensive escaping. Generic Math: Provided a more robust system for working with numeric types across generics. C# 8.0 (2019) Required Members: Ensured that certain Introduced: members are initialized during object Nullable Reference Types: Improved creation, further improving immutability nullsafety by distinguishing between practices. nullable and non-nullable reference types. IMPACT OF.NET CORE A MINIMAL C# PROGRAM MUST INCLUDE: AND.NET 5+ 1. A namespace (to organize code and NET Core Introduction (2016) avoid name conflicts) 2. A class (the building block of C# NET Core Introduction (2016) Microsoft programs) introduced.NET Core to allow C# and.NET 3. A Main method (entry point of the to be cross-platform (Windows, macOS, application) Linux). This was a shift from the Windows- only.NET Framework..NET 5 (2020) and Beyond.NET 5 (2020) and Beyond With the release of.NET 5, Microsoft unified.NET Core and.NET Framework under a single platform. This allowed C# to be used seamlessly across different platforms and Explanation of the Example: environments, including web development, desktop applications, mobile development, 1.using System; This directive imports the cloud services, and even game development System namespace, which provides through Unity. essential classes like Console. It allows us to use its functionalities without fully qualifying the names. MODERN USE AND 2.namespace HelloWorldApp The namespace is used to group classes and FUTURE OF C# organize code. In larger programs, C# continues to be a versatile and evolving namespaces help avoid naming conflicts. language, widely used in enterprise 3.class Program The class keyword defines applications, web development (with a new class. In C#, everything is ASP.NET), mobile apps (via Xamarin), and encapsulated in classes. Program is the game development (with Unity). Microsoft’s name of the class that contains the Main ongoing updates ensure that C# remains method. modern, flexible, and competitive with newer languages. 4.static void Main(string[] args) The Main method is the entry point for every C# As of now, C# is evolving towards console application. supporting even more functional programming features, enhancing When the program runs, execution starts performance, and simplifying development here. for cloud-native applications. static: The method is called on the class itself, not on an instance of the class. BASIC STRUCTURE OF A C# PROGRAM  void: The method does not return a value. string[] args: Represents command-line arguments passed to the program. 5.Console.WriteLine("Hello, World!"); This line prints the string "Hello, World!" to the console. Console is a class in the System namespace that provides methods for input and output. COMMENTS / VARIABLES AND DATA TYPES / OPERATORS FUNCTIONS AND METHODS Methods are blocks of code that perform specific tasks. The Main method is an example of this. SUMMARY OF C# SYNTAX FEATURES Case-sensitive: C# differentiates between main and Main. Statements end with a semicolon: Each line of executable code is typically followed by a ;. Code is organized in classes: Even the simplest C# program needs at least one class. COMMON ERRORS IN C# SYNTAX Missing Semicolon: Forgetting to terminate a statement with a semicolon will result in a compile-time error. Case Sensitivity: Misnaming method or variable identifiers (e.g., using main instead of Main). Mismatched Braces: Every {must have a corresponding }.