Nieuw in Visual Basic'NET Whidbey

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Nieuw in Visual Basic "Whidbey" Alex
ThissenTwice IT Training
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Agenda

• Visual Basic "Whidbey" design goals
• Language enhancements
• IDE enhancements

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Agenda

• Visual Basic "Whidbey" design goals
• Language enhancements
• IDE enhancements

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Visual Basic.NET design goals

• Increase productivity
• Do more with less code and fewer clicks
• Half development time and 50 less code
• Full access to .NET Platform
• New language features
• MSBuild and Yukon managed procedures
• Writing correct code
• Design-time expression evaluation
• Error correction with Smart Tags à la Office

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Improved Debugging Cycle

• Edit and Continue is back
• Change code without stopping or re-starting your
  debugging session
• Fix issue while code is executing in debugger
• Visual indication of "legal" and "illegal" edits
• Access to debugger values
• Debugger visualizers
• Enhanced data tool tips
• Formatted debugger output windows

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Improved Debugging Cycle

• Improved exception interaction
• Ability to continue after an exception
• Break in the debugger on exception states (First
  Chance, Unhandled and User-unhandled)
• New Exception Assistant
• Provides access to exception details
• Includes troubleshooting tips for handling the
  exception

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Configuration and Settings

• Basic support in VS 2002 and 2003
• App.config contains settings
• Framework for reading settings
• Section handlers for custom settings
• Huge improvements in Whidbey
• Framework classes support read/write
• Strongly-typed access to settings
• IntelliSense for settings
• Choose app-scoped or user-scoped settings
• Works in partial trust
• Validation model
• Shared infrastructure across client and web

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Settings architecture

• Extensible provider model
• Customizable
• At the provider level
• By writing custom settings classes

SettingsBase
ApplicationSettingsBase
WindowsApp1Settings
My.Settings
Provider Interface
LocalSettings
Remote
SqlServer
Custom
Access
Custom
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Settings
MyApp.exe.config ltapplicationSettingsgt lt/applic
ationSettingsgt

• Designer allows
• Creating, modifying, deleting entries
• Type of entry for strong typing
• Choosing user-scoped or app-scoped
• Default value
• Different profiles
• Special support for
• Connection Strings
• Web service proxies
• Visual Studio will automatically create settings

piet.config ltuserSettingsgt lt/userSettingsgt
karin.config ltuserSettingsgt lt/userSettingsgt
jan.config ltuserSettingsgt lt/userSettingsgt
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Agenda

• Visual Basic "Whidbey" design goals
• Language enhancements
• IDE enhancements

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DEMO

• Various new language features

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Partial Types

• Single Structure or Class in multiple files
• Separate designer generated from custom code
• Factor implementation
• ASP.NET now uses code-beside instead of
  code-behind
• Large interfaces implementation

Public Class MyDataSet Inherits
System.Data.DataSet 'Generated code End
Class Expands Class MyDataSet 'Expands might
become Partial Sub ExtraMethod() 'My code
End Sub End Class
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Explicit Array Bounds

• You can now specify the lower and upper bounds in
  the declaration
• But arrays are still zero based

Visual Studio.NET 2002, 2003Dim x(10) As
Integer Avoid confusion (for C programmers,
e.g.) Dim y(0 To 10) As Integer
Tip Create non-zero based array using
Array.CreateInstance
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Using Statement

• Fast way to correctly release resources
• Object "being used" must implement IDisposable
  interface
• Runtime will call Dispose method when Using block
  goes out of scope
• Compiler creates Try, Catch, Finally block

Using block disposes of resource Using objSR As
New StreamReader(strFileName) While
objSR.Peek() gt 0 Console.WriteLine(objSR.Read
Line()) End While 'StreamReader will be
disposed automatically End Using
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Continue Statement

• Skips to next iteration of loop
• Loop keyword specifies which iteration in case of
  (multiple) nested loops
• Continue For, Continue While
• Continues nearest enclosing loop

For index As Integer 0 to MyArray.Length
While MyArray(index) gt 100 If MyArray(index)
0 Then To next iteration of
index Continue For End If
CalculateValue(MyArray(index)) End While Next j
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Global Keyword

• Provides access to root, empty namespace
• Complete name disambiguation
• Better choice for code generation

Namespace SampleApp Class Form1 Inherits
Windows.Forms.Forms Sub LastName(nm As
String) Global.Microsoft.VisualBasic.Left(nm
) End Sub End Class End Namespace
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Property accessor accessibility

• Provides granular control over accessibility to
  getter and/or setter of property
• ExampleA read-only property can still have a
  setter, available only from within the class

Property Age() As Integer Get Return Me.age
End Get Private Set (ByVal Value As
Integer) If Value lt 0 Then Throw New
ApplicationException(Mistake) End If Me.age
Age End Set End Property
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Unsigned Types

• Unsigned integers are now intrinsic types
• Syntactic equivalent to System.UInt16, UInt32,
• Better support for overload resolution
• Convenient for Interop scenarios
• Easier Win32 API calls and translation

Dim sb As SByte -4 Dim us As UShort Dim ui As
UInteger Dim ul As ULong Full support in Visual
Basic modules If IsNumeric(ui) Then Should now
return True End If
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Operator Overloading

• Create your own operators, -, , , , , gt, lt,
  , CType, Not, IsTrue, IsFalse
• Operators are Shared methods
• Method signature must include at least one
  reference to enclosing type

Public Class Point Public x, y As Integer
Public New(ByVal x As Integer, Byval y As
Integer) ... Public Shared Operator (p1 As
Point, p2 As Point) _ As Point Return
New Point(p1.x p2.x, p1.y p2.y) End
Operator End Class
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Generics

• CLR based, compile-time and type-safe way to
  reuse code for different data-types
• Similar to C templates, but not same
• No compiler code generation!
• Lots of goodness
• No boxing and unboxing
• Compile-time checking of types used
• Generic collection classes in .NET Framework
• System.Collections.Generic namespace
• Dictionary, HashTable, List, Stack, etc.

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DEMO

• Generics

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Agenda

• Visual Basic "Whidbey" design goals
• Language enhancements
• IDE enhancements

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Application Designer

• One stop shopping for app settings
• Resources
• Application and user settings
• References
• Version Info
• Deployment
• Easier to find
• Non-modal window for better usability

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My. Classes

• Shortcuts into .NET Framework
• Common classes
• Application level version of Me
• Simple, flat hierarchy to work with
• Visual Basic.NET only!

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My. Classes

• My.Application
• Make application-related properties more
  accessible
• Allow commonly referenced services and classes to
  be enabled easily
• Provide a more manageable framework for
  application startup and shutdown.
• My.Computer
• Access to host computer's properties and hardware
  resources
• Audio, Printer, Screen, Keyboard, Mouse,
  Registry, File System, Serial Ports, Network,
• My.User
• User Login Name, Domain Name, Display Name,
  Roles,

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My. Classes

• Application level version of Me
• My.Forms
• My.Forms.Form1.Show
• My.WebServices
• My.WebServices.MSDN.Search(VB)
• My.Resources
• PictureBox1.Image My.Resources.Logo
• My.Settings
• My.Settings.User.FormLocation Me.Location

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DEMO

• My. Classes

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Symbolic Rename

• Quick way to change identifiers
• Rename all cases of TextBox1
• Type declarations declaration
• Variable
• Events
• More precise than text replacement
• Doesnt affect comments
• Working on other refactoring features
• Create method

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Asynchronous calling

• Easier way to call slow background tasks
• Model asynchronous calls as events
• PictureBox1.LoadAsync(url)
• PictureBox1_LoadCompleted(, )
• Completion routine is on main thread
• Web service proxies
• Supports progress, cancellation
• Background worker component

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Background Worker
Structure BackgroundArgs Dim x, y As
Integer End Structure Private Sub
Button1_Click() Handles Button1.Click Dim
args As BackgroundArgs BGW1.RunWorkerAsync(arg
s) End Sub Private Sub BGW1_DoWork() Handles
BGW1.DoWork This is run on a background
thread Dim args As BackgroundArgs args
CType(e.Argument, BackgroundArgs) e.Result
SomeLengthyOperation(args.x, args.y) End
Sub Private Sub BGW1_RunWorkerCompleted()
Handles result e.Result End Sub
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DEMO

• BackGroundWorker component

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Code Snippets

• Reusable pieces of code
• Editor to create and modify snippets
• Customization placeholders
• Context-aware in code editor
• Includes required project references and file
  imports
• Final release should include 500 task oriented
  snippets
• Extensible Architecture
• Specify multiple snippet stores (local, network
  share, etc.)

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Visual Basic Warnings

• Overlapping catch blocks or cases
• Recursive property access
• Unused Imports statement
• Unused local variable
• Function, operator without return
• Reference on possible null reference
• Option Strict broken down
• Late binding
• VB Style Conversions

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Summary

• Visual Basic "Whidbey" improves framework
  productivity
• Improves navigation of the Framework
• 50 less code for common tasks
• Visual Basic "Whidbey" enables building robust
  applications in less time
• Identify and fix errors before you build
• Provides the most productive Visual Basic
  debugging environment yet!

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Other resources and information

• http//msdn.microsoft.com/vbasic/whidbey
• Newsgroup microsoft.public.dotnet.vb
• http//communities.microsoft.com/newsgroups/defaul
  t.asp?icpwhidbeyslcidus
• Blog www.panopticalcentral.net
• Send feedback to vswish_at_microsoft.com
• Visit us at the Twice IT booth!!

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Questions and Answers

• ?