.NET Framework Library

1. A language independent universe of classes and components for your applications .NET Framework Library

2. Objectives • Provide an overview about various aspects of the .NET framework libraries not covered elsewhere in the Microsoft .NET Developer Tools Readiness Kit

3. Contents • Section 1: Introduction • Section 2: The System Namespace • Section 3: Collection Classes • Section 4: I/O and Networking • Section 5: Process Management • Section 6: Miscelleaneous Services • Summary

4. Section 1: Introduction • Looking Back • The Microsoft .NET Framework Library

5. Looking Back • Language Dependent Runtime Libraries • C-Runtime library • C++ Standard Template Library • Visual Basic Runtime • API holes plugged with ActiveX controls • Discriminatory access to functionality • Many APIs unsupported by Visual Basic • Advanced tasks often require C/C++ • Core functionality scattered all over Windows • ActiveX controls, System DLLs, SDKs, IE

6. The .NET Framework Library • One-stop, well-organized class framework • OS-independent subset submitted to ECMA • Standardization backed by Microsoft, HP, Intel • Subset includes most things covered here • http://msdn.microsoft.com/net/ecma • Integrates all current Windows technologies • Everything in one place – for all languages • Windows Forms, GDI+, Printing for Windows Dev • Web Forms, Web Services, Networking for Net Dev • Supports Active Directory, WMI, MSMQ, Services

7. Section 2: The System Namespace • System.Object • The not-so-primitive "primitive" types • String and text classes • Dates, times and calendars • System console support

8. The Root of Everything .NET: Object • Base class for each and every type • Inheritance from System.Object is typically implicit • All simple and complex types share the same base • Single base-class makes framework consistent • Collection classes can be used for everything • Intrinsic model for handling variant types • Strongly typed. No pointers, no structures • Much less error prone than COM's VARIANT type • System.Object is a reference type • Value types (internally) inherit from ValueType • Special class derived from Object

9. System.Object's Methods 1/2 • bool System.Object.Equals(Object o) • Reference identity for reference types (default) • Overridden for value types to test value identity • void System.Object.Finalize() • To be overridden by subclasses • Called when object is garbage collected • int System.Object.GetHashCode() • i.e. used with System.Collections.HashTable • Should be overriden to return good hashes • Good hash distribution speeds up hash tables • Default implementation: Identity-based hash

10. System.Object's Methods 2/2 • System.Type System.Object.GetType() • Retrieves the type object for the object's class • GetType() is the entry point for .NET Reflection • System.Object System.Object.MemberwiseClone() • Creates a exact clone of "this" object • Works through Reflection with any class • System.String ToString() • To be overriden; Returns text representation • Default returns qualified name of "this" class • Not designed for user messages (use IFormattable)

11. The "Primitive" Types • Traditionally perceived as "magic" or "special" • There is no primitive-type magic-ness in .NET! • Very SmallTalk-like model • "Primitive" types are regular framework types • However, still exposed as language-intrinsic types • C#: bool, int, long, string, double, float • Visual Basic.NET: Boolean, Integer, String • "Primitives" are mostly value-types • Exception: System.String is reference type • "Primitive" Types are not so primitive anymore • Full featured classes, rich functionality

12. Integer Numerics • System.Int16, System.Int32, System.Int64 • Standard integer (whole number) types • 16,32 and 64 bit wide. Highest bit is sign • Int32 is typically default language-mapped Integer • Implemented framework interfaces • IFormattable: locale specific text formatting • IConvertible: standard conversion into other core types • IComparable: standard value-comparison with other objects • Parse() method provides rich from-text conversions • System.UInt16, System.UInt32, System.UInt64 • Unsigned equivalents

13. Floating Point Numerics 1/3 • System.Single, System.Double • IEEE 754 floating point numbers • As used in most common programming languages • Values internally represented as fractions (narrowed values) • Good for scientific/technical use, not for business numerals • System.Single: single precision, 32-bit • System.Double: double precision, 64-bit • IFormattable, IComparable, IConvertible

14. Floating Point Numerics 2/3 • System.Decimal • 128 bit, 28 significant and precise digits • Good for business numerals, monetary amounts • IFormattable, IComparable, IConvertible • System.Double, System.Single specials • Support positive and negative infinity • PositiveInfinity and NegativeInfinity constants on class • Can represent not-a-number (NaN) values • NaN constant on class. NaN always compares false

15. Floating Point Numerics 3/3 • System.Decimal specials • Static value manipulation methods • Abs(d), Negate(d) – Positive/Negative sign • Truncate(d), Floor(d), Round(d,n) – Fractional part • Static arithmetic methods • Add(d,d), Multiply(d,d), Subtract(d,d),Divide(d,d),Mod(d,d) • All equivalent operators are defined for the class

16. Doing Numerics: System.Math • System.Math class mainly supports IEEE types • Some operations for all numerics • Abs(), Log(), Max(), Min(), Round(), Sign() • Operations • Trigonometry: Sin(),Cos(), Tan(), Acos(), Asin() • Powers and Logarithms: Pow(), Log(), Sqrt() • Extremes: Min(), Max() • Rouning: Floor(), Ceil(), Rint(), Round()

17. System.String • System.String is the cross-language string • One storage method, one API, unified handling • Locale-aware, always Unicode • Fully-featured string handling capabilities • Forward and reverse substring searches • IndexOf(), LastIndexOf(), StartsWith(), EndsWith() • Whitespace stripping and padding • Trim(), PadLeft(), PadRight() • Range manipulation and extraction • Insert(), Remove(), Replace(), Substring(), Join(), Split() • Character casing and advanced formatting • ToLower(), ToUpper() and • Format() much like C's printf but safe

18. More Strings: System.Text Namespace • StringBuilder • Super-efficient for assembling large strings • Encoders and Decoders • Support character encoding and conversions • ASCII, UTF-8, UTF-7, Windows Codepages • Unicode encoder for full UTF-16 compliant streams • Encoder can write and decoder detect byte-order marks • Supports big-endian and little-endian Unicode encoding

19. Other Core Types • System.Byte, System.SByte – Single byte numeric • System.Char – Single Unicode character • System.Boolean – True or False logical value • System.Guid • 128-bit, universally unique identifier • Built-in generator: System.Guid.NewGuid() • Intrinsic conversions from and to strings • The "Nothings" • System.DBNull – database-equivalent NULL type • System.Empty – like COM's VT_EMPTY • System.Missing – used with optional args

20. Date and Time Support • System.DateTime class for dates and times • Virtually unlimited date values (100 AD to 9999 AD) • Date and Time arithmetics built-in • AddDays(), AddSeconds() • Sophisticated, locale-aware formatting and parsing • System.TimeSpan for durations • Can represent arbitrary timespans • Can express span in arbitary units by conversion • System.TimeZone for time-zone support

21. Date and Time to the Max • System.Globalization.Calendar namespace • Correct date expressions based on local calendars • GregorianCalendar – standard western calendar • JulianCalendar • HebrewCalendar • JapaneseCalendar • KoreanCalendar • ThaiBuddhistCalendar • HijriCalendar • Two-way 2/4 digit-year windowed conversion

22. The Console • System.Console class for console I/O • Supports standard in, standard out, standard error • Writing to the console • Write() or WriteLine() • Supports String.Format syntax • Console.Write("Snowwhite and the {0} dwarfs", 7) • Reading from the console • Read() reads on characters • ReadLine() reads one full line

23. Other System Goodies • System.URI class • Two-way parsing and construction of URIs • System.Random class • Random number generator • System.Radix class • Numeric base-system conversions (eg. Dec/Hex) • System.Convert class • One-stop place for core type conversions

24. Section 3: Collection Classes • Arrays • Collection Interfaces • The Collection Classes

25. The Array • Only collection outside Collections namespace • System.Array class • Mapped to language-intrinsic arrays • Polymorphic, stores System.Object elements • Arbitrary number of dimensions, lengths • Specified at creation time (CreateInstance) • After construction, array dimensions are fixed • Supports sorting • Self-comparing IComparable objects • External comparisons with IComparer • Supports binary searches on sorted arrays

26. Collection Interfaces 1/2 • IEnumerable • Implements enumerable value set • GetEnumerator() returns IEnumerator iterator • IEnumerator: Current, MoveNext(), Reset() • ICollection (inherits IEnumerable) • Basic collection interface: Count(), CopyTo()

27. Collection Interfaces 2/2 • IDictionary (inherits ICollection) • Basic association container interface • Keys / Values table implementation • Add(), Remove(), Contains() and Clear() methods • IList (inherits ICollection) • Basic list container interface • Add(), Remove(), Contains() and Clear() methods

28. Collection Classes 1/3 • System.Collections.ArrayList / ObjectList • Dynamic arrays implementing IList • Can grow and shrink in size (unlike System.Array) • System.Collections.BitArray • Super-compact array of bits • System.Collections.HashTable • Fast hash-table implementing IDictionary • There is no Dictionary class. Use HashTable • System.Collections.SortedList • Auto-sorted, string-indexed collection

29. Collection Classes 2/3 • System.Collections.Stack • Stack implementation with Push() and Pop() • Still, fully enumerable (IEnumerable) • System.Collections.Queue • Queue with Dequeue() and Enqueue() • Fully enumerable

30. Collection Classes 3/3 • System.NameObjectCollectionBase • Abstract class, indexed view on Hashtable • Combines indexed order with Hashtable-speed • Base for quite a few subsystem collections • System.NameValueCollection • Comma separated string lists for same key entries

31. Section 4: I/O and Networking • Directories and Files • Streams, Stream Readers and Stream Writers • Isolated Storage • Networking Support

32. Directories and Files • Fully object-oriented way to explore the file system • System.IO.Directory represents a directory • GetDirectories([mask]) gets subdirectories • GetFiles([mask]) gets contained files • System.IO.File represents a file • Can construct directly by providing a path • Or returned from GetFiles() enumeration • Unifies file system entries and stream access! • All Open...() methods return System.IO.Stream • Open(), OpenRead(), OpenWrite(), OpenText()

33. Streams • Abstract base-stream System.IO.Stream • Read(), Write() for basic synchronous access • Full asynchronous support • Call BeginRead() or BeginWrite() and pass callback • Callback is invoked as soon as data is received. • Asynchronous call completed with EndRead()/EndWrite() • System.IO.FileStream • Can open and access files directly • Actual type returned by File.Open() • System.IO.MemoryStream • Constructs a stream in-memory

34. Stream Readers 1/2 • Higher-Level access to Stream reading functions • System.IO.BinaryReader • Designed for typed access to stream contents • Read methods for most core data types • ReadInt16(), ReadBoolean(), ReadDouble(), etc. • System.IO.TextReader • Abstract base class for reading strings from streams

35. Stream Readers 2/2 • System.IO.StreamReader (implements TextReader) • ReadLine() reads to newline • ReadToEnd() reads full stream into string • System.IO.StringReader (implements TextReader) • Simulates stream input from string

36. Stream Writers • High-level access to Stream writing functions • System.IO.BinaryWriter • Designed for typed writes to streams • >15 strongly typed overloads for Write() method • System.IO.TextWriter • Abstract base class for writing strings to streams • Includes placeholder-formatted strings • System.IO.StreamWriter (implements TextWriter) • Writes strings to streams with encoding support • System.IO.StringWriter • Simulates streams-writes on an output string

37. Isolated Storage • Scoped, isolated virtual file system • Scoped to User, Assembly or Application Domain • Great as temporary storage location • Sandboxed environment • Storage location managed by runtime system • System.IO.IsolatedStorage.IsolatedStorageFile • Container for virtual file system • Static methods for access/creation of storages • [...] IsolatedStorageFileStream • Stream implementation on isolated storage • Behaves like any ordinary file

38. The Net in .NET: System.Net • System.Net contains all network protocol support • Low-level support for IP sockets and IPX • Application level protocol implementations (HTTP) • Authentication methods for HTTP • Basic, Digest, NTLM Challenge/Reponse • Full cookie support for HTTP

39. Request and Response Classes • System.Net.WebRequest class • Base class for network request/response protocols • Abstract base for HttpWebRequest • Create requests through WebRequest.Create() • Plug in new protocol handlers with RegisterPrefix() • System.Net natively supports HTTP and HTTPS • Request can be populated through stream • WebRequest.GetRequestStream() • Request is executed on GetResponse() • Data through WebResponse.GetReponseStream()

40. Protocol Support Classes • Manage connectivity through ServicePoint • Connections managed by ServicePointManager • Per-Endpoint configuration of connection params • System.Net.EndPoint information in ServicePoint • Base class for endpoints • System.Net.IPEndPoint • Represents an IP endpoint with IPAdress and port • System.Net.IpxEndPoint • Represents an IPX endpoint • System.Net.DNS • Access to DNS nameservers and name resolution

41. IP Sockets • System.Net.Sockets.Socket for raw sockets • send with Send(), receive with Receive() • Socket.Connect() connects to EndPoint • Supports TCP, UDP, IP Multicast, IPX and others • Socket.Bind() and Socket.Listen() create listener • High-Level wrappers for TCP, UDP • TcpClient, UdpClient provide NetworkStream • Usable with System.IO's stream readers/writers • TcpListener implements TCP listener • Can pickup connection requests as Socket or TcpClient

42. Section 5: Process Management • Process control • Threading support

43. Processes • System.Diagnostics.Process class • Allows creating/monitoring other processes • Monitoring: All Task-Manager stats accessible • Process.Start() equivalent to Win32 ShellExecute • Arguments are set via ProcessStartInfo class • Supports shell verbs (print,open) • Supports waiting for termination (WaitForExit) • Can register event handlers for "Exited" event • Explicit termination supported in two ways • Rambo method: Kill() • Nice-guy method: CloseMainWindow()

44. System.Threading.Thread • Every .NET application is fully multi-threaded • No more haggling with threading models • Except in COM/Interop scenarios, of course • Trade-Off: Must take care of synchronization • System.Thread represents a system thread • Threads are launched with entry point delegate • Object-oriented threading model • No arguments passed to entry point • Thread launch-state is set on object hosting the delegate • ThreadPool implicitly created for each process

45. Creating Threads // instantiate class that will execute on threadPulsar pulsar = new Pulsar();// create delegate for entry point on instance ThreadStart threadStart = newThreadStart(pulsar.Run);// create new thread object and start the threadThread thread = new Thread(threadStart); thread.Start(); // do other things ...// wait for thread to complete thread.Join();

46. Thread Synchronization Monitor • System.Threading.Monitor class • Supports Wait/Pulse coordination model • One thread enters Wait() • Other thread calls Pulse() to release Wait() lock • Similar to Win32 critical sections model • Can synchronize on every managed object // enter critical section or waitMonitor.Enter(this);// perform guarded action internalState = SomeAction( );// release lock Monitor.Exit(this); // C# intrinsic equivalentlock (this) { internalState = SomeAction( );}

47. More Threading • Synchronization with WaitHandle • Mutex: Single synchronization point • Mutex.WaitOne() waits for Mutex to be available • Mutex.ReleaseMutex() releases mutex lock • AutoResetEvent, ManualResetEvent • *.WaitOne() waits for event to be signaled • Set() sets event, Reset() resets event state • Static WaitAny() / WaitAll() for multiple waits • Threading Timers for timed callbacks • Interlocked class for lightweight locking • Interlocked.Increment( ref i )

48. Section 6: Advanced Services • Windows 2000 Services • Diagnostics and Profiling

49. Windows 2000 Services • System.Management • Windows Management Instrumentation (WMI) • System.Messaging • Microsoft Message Queue • System.DirectoryServices • Active Directory Services • System.ServiceProcess • Expose .NET applications as Windows Services

50. Windows 2000 Event Log • System.Diagnostics.EventLog class • Reading event logs • Static EventLog.GetEventLogs() gets all machine logs • EventLog.Log indicates the type of event log • Application, System, Security, etc. • EventLog.Entries retrieves all entries for a log • EventLog.EventLogEntryCollection • Contains EventLogEntry elements • Can register event handler to monitor log continuously • Writing event logs • Create new source with CreateEventSource() • Write to log with WriteEntry()