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Chapter 1. Getting Started with VB .NET. Objectives. Learn about VB .NET and the characteristics of a VB .NET solution Start and configure VB .NET Explore the elements of the development environment Learn how to access Help Open a VB .NET solution
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Chapter 1 Getting Started with VB .NET
Objectives • Learn about VB .NET and the characteristics of a VB .NET solution • Start and configure VB .NET • Explore the elements of the development environment • Learn how to access Help • Open a VB .NET solution • Explore the tool windows and operating modes of VB .NET
Introducing Visual Studio .NET (1) • Visual Studio .NET is an integrated development environment • Development environment supports three different languages • Visual Basic • Visual C++ • C# (pronounced C sharp) • New to Visual Studio .NET • Note that Visual Interdev is obsolete. Functionality included with other Visual Studio .NET products
Introducing Visual Studio.NET (2) • Applications (called solutions) developed using a developer interface called the Microsoft Development Environment (MDE) • VB .NET supports different types of applications created with the following tools • Windows Forms used to create desktop applications • Web Forms used to create programmable Web pages • Web Services process client – server requests
Differences Between VB 6 and Visual Studio .NET • VB 4, 5, and 6 were backward compatible • VB .NET is not backward compatible • VB 6 programs require significant modification to run under VB .NET • VB .NET incorporates new object oriented programming features • VB .NET adheres to the Common Language Specification (CLS) for language interoperability • ADO.NET replaces ADO • ADO.NET operates better with Web applications
Facts About Programming Languages (1) • Programminglanguage made up of words forming statements • A Statement expresses a complete thought or idea • Similar to an English sentence • Statements grouped into procedures • A procedure is similar to a paragraph in English • Procedures grouped into a module • Modules contain one or more procedures • Modules correspond to physical disk files • Module files have the suffix .vb.
Facts About Programming Languages (2) • A program contains statements, grouped into procedures, in one or more modules • VB .NET calls a program a solution • Each solution is stored in its own folder • Solution folder contains sub folder • Solution folder contains all of the files that make up the solution
Program Relationships Public Class frmMain Inherits System.Windows.Forms.Form Private components = New System.ComponentModel.Container End Class Module filefrmMain.vb Public Sub New() End Sub Procedure MyBase.New()InitializeComponent() Executablestatements Public Sub InitializeComponent() End Sub Procedure Me.Text = "Chapter 1 – Completed Example Executablestatement Public Class frmDialog . . .End Class Module filefrmDialog.vb
Types of Statements • Declarationstatements define the names of data and procedures • The following statements declare a variable and a procedurePrivate mstrCustomerName As StringPrivate Sub InitializeComponent()End Sub • Executablestatements perform a specific action • The following statement closes the form named frmMainfrmMain.Close()
Syntax • Programming statements adhere to rules known as syntax • Statements must be exactly correct • VB .NET cannot interpret statements with typographical or spelling errors • Incorrect statements will cause a syntaxerror • Syntax errors occur when a statement violates the rules of the language Private mstrCustomerName As Strung frmMain.Closed()
VB .NET Programming Concepts • VB .NET solutions have the same characteristics as other programs • Window is a rectangular area on the desktop • Win Form (form) contains buttons and boxes • Buttons, boxes, and the form itself are all windows • Solutions contain 1 or more forms • Collection of forms, buttons, and boxes form the user interface • User interface represents what the user sees and how the user interacts with the solution
Object Oriented Terms (1) • Information hiding – Expose only essential information and hide inner logic • Encapsulation – Integrate (package) data and processes that act on data together • Inner logic is hidden from the developer • Inheritance – Create new objects from existing objects • Inherit one form from another form • Polymorphism – Multiple procedures of the same name perform different tasks • Capable of taking many forms
Object Oriented Terms (2) • Programmingobject mimics the behavior of a real-world object • Buttons on a form perform a task when clicked • Some objects are visible to the user – others are not • Objects are created from classes • Multiple objects can be created from the same class. For example, create multiple buttons on a form • A class is a blueprint (template) for an object • Buttons on a form created from the Button class • Boxes created from the TextBox class
The Technical View of a VB .NET Solution (1) • An object has: • Predefined behaviors or settings called properties • Properties exist to define the size and position of a button on a form, for example • Methods represent the actions an object can perform • Events allow messages to be sent to a solution • Write code in event handlers also known as event procedures • When the user clicks a button, statement in the corresponding event handler execute
The Technical View of a VB .NET Solution (2) • Use controls to create objects appearing on a form • A control created on a form is called a control instance • Button control is a button the user can click • Label control displays text but cannot receive input • OpenFileDialog control displays a standard dialog box allowing user to select a file • PictureBox control displays pictures • All control instances created from their respective class
Sample of VB .NET Controls Label control instance to display file name Label control instance to display a descriptive prompt PictureBox control instance to display graphical image Buttons when clicked perform an action OpenFileDialog control instance has no visual interface and appears in a tray at the bottom of the form
Starting VB .NET Microsoft Visual Studio.NET 7.0 Start button
Configuring VB .NET (1) • VB .NET supports two operating modes • Tabbed documents environment • Docked windows appear along edge of the MDE • Docked windows can be temporarily hidden • Floating windows appear anywhere on the desktop • Windows can be autohidden along any edge of the MDE • Multiple document interface • Appearance similar to Excel • Not used in this book
Configuring VB .NET (2) • On the Menu bar, click Tools, and then click Options to display Options dialog box • General tab sets environment (tabbed documents or MDI mode) • Projects and Solutions tab sets default folder for projects and when changes are saved
VB .NET Options Dialog Box – General Tab Select folder Active page highlighted
VB .NET Options Dialog Box – Projects and Solutions Tab Default project location
VB .NET Window Types Document window Docked window Autohidden window Floating window
Configuring the Menu Bar and Toolbar • Multiple regions display toolbars • Regions appear along any edge of the MDE • Individual toolbars can be hidden or made visible depending on task at hand • Use Customize dialog to configure toolbars • Floatingtoolbars appear anywhere on the desktop • Dockedtoolbars anchored along any edge of the MDE • Usually they appear below the menu bar though
Docked and Floating Toolbars Docked toolbar Floating toolbar Toolbars docked along bottom of MDE
Document Windows • Appear on group tabs and correspond to the individual files that make up a solution • Win Form Designer used to create the user interface • Code Editor used to write statements in event handlers • Only one document window visible at a time • Select window on group tab to activate desired document window • Buttons to the right of a group tab navigate between document windows and close them
Tool Windows • The same tool windows are used in the creation of all VB .NET solutions • Solution Explorer groups all elements needed to build and run a solution • Properties window allows developer to manage the appearance of each object • Help windows are also tool windows • Tool windows can be: • Docked – appearing along an edge of the MDE • Autohidden – hidden along an edge of the MDE • Floating – appearing anywhere on the desktop
Document Windows and Tool Windows Document windows appear on tab group Close active document window Solution Explorer is a tool window (appearing as a docked window
Configuring Tool Windows (1) • Make a window float by right-clicking on the title bar and select Floating • Autohide a window by first docking the window. Right-click the title bar and select Autohide • Dock a window by right-clicking the title bar and select dockable. Drag the window to an edge of the MDE • Configure windows as desired so that they best fit your needs
Configuring Tool Windows (2) Docked window Autohidden windows appear along an edge of the MDE
Getting Help • VB .NET supports four primary help windows • Index – alphabetical list of contents • Contents – table of contents organized by topic • Search – locate topics by keyword • DynamicHelp – new to .NET • Display topics based on active window and current task • Topics that appear in the Dynamic Help window will change as you navigate from window to window • Help filters restrict information displayed
Help – Index Index tab Filter applied Applicable topics
Help – Contents Book expanded Topic
Help – Search Search text Search results
Help – Dynamic Help Dynamic Help Window
Opening a VB .NET Solution • Click File, and then click OpenSolution Select folder Enter solution name Click to Open solution
Organization of a VB .NET Solution • Solution file is at the heart of the application • Controls how solution will be translated into executable file • Controls how application will be distributed • File suffix is .sln • Solution file references one or more project files which: • Store global information • List the other files in the project • List references to namespaces
Form Modules • Projects can contain multiple forms • Each form stored in a form module • Form module contains code to create control instances • Also contains code written by the developer to perform tasks • File suffix is .vb • Do not change file suffix or VB .NET will not be able to locate files
Elements of a Solution solution file form module frmDialog.vb form module frmMain.vb class module clsDemo.vb project fileComplete01.vbproj standard module stdDemo.vb Bin folder contains compiled solution Obj folder contains temporary files text file solution items icon files miscellaneous files
The Solution Explorer • Groups projects and modules comprising a solution
Properties Window (1) • Property is a characteristic of an object • Color, caption, screen location • Set properties using the Properties window • Name column lists property • Value column contains current value • Display properties alphabetically or by category • Description of selected appears at the bottom of the window • Description section may be hidden
Properties Window (2) Object list box Toolbar area Selected Font property has subproperties Description area
Toolbox Visual controls appear in the Toolbox
Operating Modes • Three operating modes • In run mode VB .NET is executing the program • Program appears as the user will see it • In design mode you assume the role of the developer • In break mode solution is temporarily suspended • Use for debugging • Refer to Appendix A for information on debugging
Running a Solution • Press Start button on the Debug toolbar • Solution runs as the user will see it • Press Stop Debugging button on the Debug toolbar to end the solution and return to design mode