.NET Tech Talk Series

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.NET Tech Talk Series
Intro to C

• Wednesday, February 5th, 2003

• Michael Dunn ( mdunn_at_cs.drexel.edu )
• Drexel University Student Ambassador to Microsoft
• Mid-Atlantic Student Ambassador Team Lead
• MCS Society Vice President

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Agenda

• Introduction
• What is C?
• A first look at C
• Code demo
• C features
• Conclusion
• Questions
• Raffle

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Introduction

• Third in a series of .NET Technical Talks
  sponsored by Microsoft and Drexels Math and
  Computer Science Society.
• Summary of last talk
• Keep your old C code, and inter-operate with
  .NET using C.NET to get access to the class
  library, security, and garbage collection.
• As usual
• Please remember to fill out evaluations you
  cant win a door prize without a completed form
• Please hold detailed questions till the end

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What is C?

• A new object oriented language
• Syntax based on C
• Similar to C and Java
• Used to write .NET software
• Software that targets the .NET Framework is
  called managed code
• C gains much from the .NET Framework
• Internet oriented platform
• JIT compilation
• Automatic memory management
• Security, type-safety
• Framework Class Library

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What is C?

• Existing languages are powerful. Why do we need
  another language?
• Important features are spread out over multiple
  languages
• choose between pointers (C)
• or garbage collection (Java)
• Old languages new features poor syntax
• Garbage collection in C?
• Event-driven GUIs in Java?

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What is C?

• Derived from the features and syntaxes of other
  languages
• The safety of Java
• The ease of Visual Basic
• The power of C

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What is C?

• The safety of Java
• 100 object oriented
• Automatic garbage collection
• Array bounds checking at runtime
• Strict type checking
• Structured exception handling

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What is C?

• The ease of Visual Basic
• First class support for properties
• First class support for events
• For-each loops

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What is C?

• The power of C
• Enumerations
• Operator overloading
• Mathematical, Indexing, and Casting
• Function pointers
• Called delegates
• Type safe
• Structs
• Option to pass parameters by reference of by
  value
• Can disable type-safety, garbage collection, and
  bounds checking
• Can directly manipulate memory with pointers

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A first look at C

• using System.Windows.Forms
• using System.Drawing
• class MyFormForm
• public static void Main()
• Application.Run(new MyForm())
• protected override void OnPaint(PaintEventArgs
  e)
• e.Graphics.DrawString("Hello World!",
• new Font("Arial", 35), Brushes.Blue, 10, 100)

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Code demo
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What is C?

• Most users think of two types of objects
• Real objects Customer, Order, etc.
• Primitive types int, float, bool
• Different expectations for each
• Real objects are more expensive to create
• Primitives always have a value
• Primitives have operator support

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What is C?

• Traditional views
• C, Java Primitive types are magic and do not
  interoperate with objects
• C offers improved extensibility and reusability
• New primitive types Decimal, SQL,
• Collections, etc., work for all types

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What is C?

• Unified type system
• All types ultimately inherit from object
• Classes, enums, arrays, delegates, structs,
• An implicit conversion exists from any type to
  type object

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What is C?

• 76 keywords
• abstract as base bool break byte case
• catch char checked class const continue decimal
• default delegate do double else enum event
• explicit extern false finally fixed float for
• foreach goto If implicit in int interface
• internal is lock long namespace new null
• object operator out override params private protec
  ted
• public readonly ref return sbyte sealed short
• sizeof stackalloc static string struct switch
• this throw true try typeof uint ulong
• unchecked unsafe ushort using virtual void while

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C.NET primer (cont.)
Compilation
Code (IL)
Source Code
Metadata
JIT Compiler
Native Code
Execution
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C.NET primer

• C.NET is _not_ a dramatically different
  language from your daddys C
• Everett C.NET will be 98 compliant with the
  ISO standard
• Everett will ship with /GS compiler flag to
  catch buffer overflows
• The syntax generally remains the same, while the
  compiler emits entirely different instructions
• Due to Intermediate Language (IL), machine
  instructions are generated at runtime

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C.NET primer

• Why use C.NET over C, or other .NET languages
• Use managed or unmanaged code
• Keep using your low-level or performance critical
  native code alongside .NET
• Lots of code already written in C
• /clr compiler switch IJW (It Just Works)
• Use cross-language debugging and all the other
  neat .NET tricks

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C.NET demo

• Live demo of C.NET with
• Visual Studio.NET 2002

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Conclusions

• C.NET targets the same lower-level developers
  as Visual C 6.
• Compile your old C code using the C.NET
  compiler to get the advantages of .NET.
• Moving toward ISO standardization

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Next tech talk

• Next week, Wednesday!
• Same time, same place
• Topic Intro to C
• More books, software and food

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Further references

• http//www.gotdotnet.com/team/cplusplus/
• http//msdn.microsoft.com/visualc/
• http//www.cplusplus.com/

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Questions / Raffle

• Send your evaluations forward!