Irwin/McGraw-Hill Copyright© 2000 by the McGraw-Hill Companies, Inc. PowerPoint® Presentation to accompany prepared by James T. Perry University of San Diego

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Ch. 1: Introduction to VB  Writing windows applications with VB  Prog. languages: procedural, object oriented, & event driven  Writing VB projects  The VB environment  Writing your first VB project  Finding & fixing errors  Visual Basic help

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Writing Windows Apps. with VB  The Windows GUI Text boxes Frame Labels Option buttons Check boxes Command buttons Image Picture box

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Graphic User Interface  Graphic User Interface (GUI) comprises –Forms –Controls –Event-driven programming

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Prog. Languages: procedural, object oriented, & event driven  The Object Model –Objects (nouns)controls –Properties (adjectives)form1.Caption –Methods (verbs)debug.print  Versions of Visual Basic –Working Model –Learning Edition –Professional Edition –Enterprise Edition

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Planning Visual Basic Projects  The three-step process for planning projects –Design the user interface Sketch the screens with forms and controls needed –Establish the objects' properties Write down the properties for each object –Plan the Basic code Write out pseudocode for actions your program will perform

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Writing Visual Basic Projects  The three-step process for writing projects –Design the user interface Create the forms and controls you previously sketched –Set the objects' properties Give each object a name and set their properties –Write the Basic code Write out Visual Basic code to carry out your application's actions

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Visual Basic Projects  Visual Basic projects create several files –Project file:.VBP Holds the names of other files in the project –Form files:.FRM Each form is saved as a separate file Form file contains a description of a form's objects and the Basic code attached to a form –Standard code module:.BAS (optional) –Custom controls:.OCX (optional) –Form information:.VBW

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill The Visual Basic Environment  Form, Project Explorer, Properties, and Form Layout Windows  Toolbox  Main Visual Basic window  Toolbar, Form location & size information  Help  Design-, Run-, and Break Time

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill The Toolbox  Tool box contents vary based on which version of Visual Basic you are running.  Toolbox contains a common set of tools across all VB versions

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill The Visual Basic Toolbar  The buttons on the toolbar are shortcuts  Toolbar buttons are a quick way to activate frequently used commands  Each button stands for a command that you can also select a the Visual Basic menu

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Writing Your First VB Project  Set up your Visual Basic workspace  Define user interface  Set properties  Write code  Visual Basic code statements  Run, save, open, modify, & print the Hello World project  Documentation

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Set Up Your VB Workspace  Set up Options to reflect these settings:

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Define the User Interface  Resize the form –Drag the lower-right handle to enlarge the form –Drag any handle in the middle of a side to enlarge the form in that direction only  Place controls on the form –Click the label tool –Click and drag the mouse (a crosshair) to place the control on the form

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Set Properties  Set the Name and Caption properties –Always set the Name property before writing code –Next, set the Caption property  The Name property identifies the object internally--so you can refer to it in code  The Caption property externally idenfities an object

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Write Code  You write code enclosed in event procedures, which respond to typical VB events. Private Sub cmdPush_Click()... (your code goes here) End Sub  VB automatically supplies the event procedure Sub/End Sub statements

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Visual Basic Code Statements  Remark statement is any code line beginning with an apostrophe  Assignment statement  End statement

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Code the Event Procedures for Hello World  Write the Push event code for the Push Me button (cmdPush)  Write the Push event code for the Exit button (cmdExit)

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Run/Save/Open/Modify the Project  Test the project: –Click Run, Start (or click the Start button on the toolbar) –Click the Push Me button –Click the Exit button  Save the project and the form  Make modifications to the form  Print the project documentation: –Form Image, Code, and Form as Text

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Finding & fixing errors  Compile (syntax) errors  Run-Time (semantic) errors  Logic errors  Project Debugging

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Naming Conventions  Objects have special prefixes that help identify the object's general type  Programmers follow the conventions because it simplifies coding and debugging  Never use default names for objects

Copyright© 2000 by the McGraw-Hill Companies, Inc.Irwin/McGraw-Hill Visual Basic Help  Help includes all of the Microsoft Developer Network (MSDN) library.  The Working Model does not contain the extensive MSDN facilities  Access MSDN online at