VBScript

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VBScript

• Eric_at_netline.be

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Microsoft Visual Basic Scaleable Solutions

• Visual Basic
• Best tool for distributed client/server solutions
• Powerful, robust, scaleable
• Creates ActiveX Controls and documents

• Visual Basic for Applications
• More sophisticated application scripting
• End-user focus, natural upgrade, superb
  integration
• Part of Office 97 and widely licensed

• Visual Basic Scripting Edition
• Great for active HTML content
• Fast, lightweight

• Control creation edition

• Standard edition
• Professional edition
• Enterprise editions

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Extending HTML
HTML
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What Is ActiveX Scripting?
A language-independent standard that defines the
relationship between a scripting host and a
scripting engine
ActiveX Scripting
Internet Explorer (scripting host)
Visual Basic Script (scripting engine)
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A Simple Solution(Pioneered by Visual Basic)

• Objects raise events for the purpose of
  coordinating their activity with the rest of the
  world
• Script code can be attached to an objects events
  to customize behavior - this is scripting

Click Event
Button Object
Sub Button_Click MsgBox Hello world End Sub
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The Scripting Spectrum

• Dynamic run-time environments have varying
  requirements -no one size fits all!
• Small scripting languages cantarget specific
  integration tasks

More coding,more like an application
Less coding,more like a document
Visual C
Visual Basic
Visual Basic Script
Internet Studio
Microsoft Office (Visual Basic for Applications)
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Visual Basic Scripting EditionA lightweight
scripting solution

• Small, fast, and safe
• Proper subset of Visual Basic for Applications
• 100 compatible with Visual Basic
• Built into Internet Explorer 3.0and Windows NT
• Cross-platform for easy mobility
• All clients, servers
• Licensable, not just for the Internet
• Free distribution

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VBScript Characteristics

• Native support for OLE
• Run time is a subset ofVisual Basic for
  Applications
• Small, fast parser and compiler suitable for code
  distributed as source text
• Small interpreter and run-time footprint are main
  design goal

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Flexible Approach To Safety

• Core engine is safe, with a limited set of
  intrinsic operations
• Unsafe or platform-dependent features such as
  file I/O and DLLs are moved into separate objects
  (to which the host controls access)
• Safety level can be adjusted in known secure
  environments, such as private nets or servers

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VBScript And Visual Basic For Applications Synergy

• VBScript is a nucleus
• Working set size is critical
• Suitable for porting to any platform
• Freely licensable
• Visual Basic for Applications adds features and
  UI
• Premier RAD environment
• Run time adds more featuresand convenience
• OLE is fundamental to both

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VBScript And Visual Basic Contrasted

• Omitted features
• Data types
• User-defined types and classes
• Named arguments
• Error trapping and DoEvents
• Goto, gosub, and select case
• Debugging and conditional compilation
• File I/O, graphics, and DLL access
• More nitssee Web page fordetails

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Terms
Script A bunch of code, or a
persistent object representing a bunch of
code Scripting engine An OLE server that
provides a class of scripts. E.g.,
vbscript.dll Scripting host An application or
other component that uses scripting
engines Script site A host-provided object that
facilitates communication with a
particular script
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Browser Methods

• RefreshRefresh view
• GoBackNavigate to the previous item
• GoForwardNavigate to the next item
• GoHomeGo to home/start page

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Browser Methods

• GoSearchGo to search page
• Open(Target, Location, NoHistory)Opens a target
• StopStops opening a target
• PrintOut()Prints the document

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Browser MethodsFrame specific

• Navigate(Hlink, OpenInNewWin, NoHistory)
• BrowseBrowse for a new folder to view
• QuitExit frame and close the open window

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Browser Properties

• IDispatch Container A pointer to the container,
  if any
• IDispatch DocumentThe document
• BSTR TypeThe type of the document
• BOOL BusyBusy flag
• BOOL VisibleWhether the browser is visible or
  hidden

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Browser PropertiesFrame specific

• BOOL FullScreen
• BOOL ToolBar
• BOOL StatusBar
• BSTR StatusText
• long Top LeftPosition of the frame window
  relative to the screen (pixels)
• long Height WidthSize of the frame window
  (pixels)

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Browser Events

• Navigate(Hlink, Cancel)Fired when a new
  hyperlink is being navigated to
• StatusTextChange(Text)Statusbar text changed
• Error()Fired when an error occurs
• Quit(Cancel)Fired when application is quiting

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Questions
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