Chapter 2 Build Your First Project A Step-by-Step Approach 2 Exploring Microsoft Visual Basic 6.0 Copyright © 1999 Prentice-Hall, Inc. By Carlotta Eaton

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.2 Objectives  Describe compilers, interpreters, source code files, pseudo code files, native code files, and executable files.  Describe the steps in building an application program.  Describe the steps in building a project with Visual Basic.  Create a Visual Basic project following the step-by-step approach.

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.3 Programmer’s Lingo Program - detailed set of instructions for a computer Programming Language - tool used to create a program; defined by semantics and syntax Semantics - the meaning of words in a language Syntax - rules for combining symbols of a language

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.4 Programmer’s Lingo Source Code (code) - program you write using a programming language Interpreter - translates and executes source code statement by statement

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.5 Programmer’s Lingo Interpreter Process

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.6 Programmer’s Lingo Compiler - translates source code into an executable file Executable file - standalone file that runs outside the Visual Basic environment; Used to distribute most Windows applications Package and Deployment Wizard (Application Setup Wizard in VB5) - creates all the files necessary to distribute your projects

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.7 Programmer’s Lingo Compiler Process

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.8 Programmer’s Lingo Object Code - intermediate step between source code and native code Native Code (machine language) -instructions the computer can execute directly Dynamic Link Library (DLL) - translates instructions in executable file at runtime

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.9 Steps in Building a Project 1. Define the Problem 2. Design and Plan 3. Build the Program 4. Run the Program 5. Test and Debug 6. Document Your Program 7. Compile and Distribute Your Program

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.10 Steps in Building a Project Step 1 - Define the Problem Decide exactly what problem you want to solve Or task you want to perform Understand what needs to be done Specification - details of your problem definition

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.11 Steps in Building a Project Step 2 - Design and Plan Most important step of the process Find a step-by-step solution to your problem Algorithm - step-by-step solution to a problem Design User Interface; draw sketches of screens, graphics, text and button

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.12 Steps in Building a Project Step 3 - Build the Program Translate your solution using the programming language Coding - writing a program in a programming language Create the user interface, set properties Write code for commands and instructions

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.13 Steps in Building a Project Step 4 - Run the Program Run the program in the programming environment Visual Basic Interactive Development Environment for VB Simply click the Start button

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.14 Steps in Building a Project Step 5 - Test and Debug Testing - running your program and looking for errors Debugging - process of removing errors from a program Bug - error in a program Repeat until your program runs as designed

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.15 Steps in Building a Project Step 6 - Document your Program Very important if program will be updated in the future Documentation - consists of notes and materials that describes a program Organize the documentation

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.16 Steps in Building a Project Step 7 - Compile and Distribute Proceed to this step only after all bugs have been discovered and removed Distribute program to end user End User - the target audience for your final program

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.17 Steps in Building a Deck 1. Define the Problem - deck for grill, table and 4 chairs 2. Design and Plan - sketch a floor plan 3. Build the Deck - oops, forgot stairs 4-5. Run, Test, and Debug - as we built 6. Document the Work - receipts and plans 7. Compile and Distribute - invite friends for a cookout to share and enjoy new deck

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.18 Critique the Process  Programming is a building process  Make-or-buy decision - build it or buy it  Look for flaws before building  Much easier and less expensive to correct flaws during specification step  Work smart; gather documentation throughout process  Test and debug to avoid dissatisfied customers and potential lawsuits

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.19 Build a Visual Basic Application

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.20 Build Your First Application Hands-On Exercise 1 Create a New Project Set Visual Basic Options Restart Visual Basic Create the Initial Screen Create the Final Screen Add an Image to the Final Screen Save Your Project Run Your Project Close the Project and Exit Visual Basic

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.21 Using the Code Editor GUI (Graphical User Interface) - forms and windows that the user sees Property - a characteristic or attribute of an object such as color and size Event - a user action such as clicking a button Code Editor window - editor specially designed to help you when writing code

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.22 Testing and Debugging  Humans are not perfect  Rarely code programs right the first time  Test to find problems  Debug to correct problems

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.23 Banner Comments ‘************************************* ‘ Programmer: Carlotta Eaton ‘ Date: June 30, 1998 ‘ Source: Hello World.vbp ‘ ID: Chapter 2 Hands-On 1 ‘ Purpose: Practice steps to create ‘ a Visual Basic project ‘ Inputs: None ‘ Returns: None ‘***************************************

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.24 Documenting Your Project  Follow Code Conventions, and Print your Code Conventions make your code easier to read and understand Use block indenting Print code and put in documentation folder

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.25 Distributing Your Project  Remove all bugs first  Create an executable file Pull down File menu, and select Make Project exe command or Use Package and Deployment Wizard (previously called Setup Wizard)

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.26 Summary...  Key terms defined such as compiler and executable file  Use a systematic process to create a Visual Basic project  Spend more time planning and designing and less time writing, testing and debugging

Exploring MS Visual Basic 6 Copyright 1999 Prentice-Hall, Inc.27 Summary Step-by-Step Process 1. Define the problem 2. Design and Plan the Solution 3. Build the Program 4. Run the Program 5. Test and Debug 6. Document your project 7. Compile and Distribute