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1、1-21Introducing Visual BasicBeginning Visual Basic1。 Introducing Visual BasicA Story About Bill and PaulBack in the early 1970s， Bill and Paul were friends at Lakeside School in Seattle， Washington。 Bill and Paul enjoyed working with computers and wrote many games they could play - games like TicTac
2、Toe and moon landing games。 These computer games were written in a computer language called BASIC （which stands for Beginners AllPurpose Symbolic Instruction Code）。 When the first small computer was developed in the mid 1970s， Bill and Paul had just started college。 They had improved their computer
3、skills by then and were able to tell that new computer how to use the BASIC language。 They actually sold their version of the BASIC language to other people （it cost 350 and was stored on a cassette tape）. They started making money selling BASIC and decided to start a company。 You may have heard of
4、their company Microsoft！ Bill is Bill Gates， who still runs Microsoft and is worth many billions of dollars, and Paul is Paul Allen， who no longer works for Microsoft, but has his own business ventures including computers and software， professional sports teams， and real estate development。Yes， the
5、first product sold by Microsoft was the BASIC computer language. Microsofts name for their BASIC language product has changed over the years， having names like GWBASIC, QuickBasic and QBasic, with the newest version being called Visual Basic. Visual Basic is one of the easiest programming languages
6、to learn。 Yet， even though it is easy to learn and to use， Visual Basic can also be used to develop very powerful computer programs。 Many computer games are written in Visual Basic, businesses use Visual Basic to manage their databases， webmasters use Visual Basic in developing web pages， and people
7、 like yourself use Visual Basic to build Windows applications they want and need in their everyday life。 In these notes， you will learn how to use Microsofts Visual Basic to write your own computer programs. You may not become a billionaire like Bill and Paul， but hopefully youll have some fun learn
8、ing a very valuable skill。Lets Get StartedLearning how to use Visual Basic to write a computer program (like learning anything new） involves many steps, many new terms, and many new skills。 We will take it slow， describing each step， term， and skill in detail。 Before starting， we assume you know how
9、 to do a few things: You should know how to start your computer and use the mouse。 You should have a little knowledge on working with your operating system （Windows 95, 98， or NT）。 You should know how to resize and move windows around on the screen. You should know how to run an application on your
10、computer by using the Start Menu. You should know how to fill in information in Windows that may pop up on the screen. You should know about folders and files and how to find them on your computer。 You should know what file extensions are and how to identify them. For example， in a file named Exampl
11、e。ext, the three letters ext are called the extension。You have probably used all of these skills if youve ever used a word processor， spreadsheet, or any other software on your computer。 If you think you lack any of these skills， ask someone for help or consult one of the many books introducing the
12、Windows operating system。 Lets get going。 And, as we said, were going to take it slow。 In this first class， we will learn how to get Visual Basic started on a computer， how to load a program （or project） into Visual Basic, how to run the program， how to stop the program， and how to exit from Visual
13、Basic。 It will be a good introduction to the many new things we will learn in the classes to come.Starting Visual BasicWe assume you have some version of Visual Basic installed and operational on your computer。 If you dont， you need to do this first. Again， this might be a good place to ask for some
14、ones help if you need it。 Over the past several years， there have been many versions of Visual Basic。 You will be able to do this class using Visual Basic 4。0 (32 bit version）， Visual Basic 5。0, or the new Visual Basic 6。0。 Throughout the notes, we will refer to Visual Basic by its abbreviation VB,
15、and you will be told what to do depending on what version of Visual Basic you are using. If you are using Visual Basic 4。0, look for the abbreviation VB4 for information particular to your version。 If you are using Visual Basic 5.0, look for the abbreviation VB5 for information particular to your ve
16、rsion。 And， if you are using Visual Basic 6。0, look for the abbreviation VB6 for information particular to your version。To start Visual Basic: Click on the Start button on the Windows task bar。 Select Programs， then Microsoft Visual Basic （where # is your version of Visual Basic）. Click on Visual Basic (where again is your version）。（Some of t
