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Intermediate Visual Basic. CISP 371 CRC Prof. Chapman. VB Capabilities. Most people think that Visual Basic is only useful if you want to build a GUI program that runs on a desktop PC. But VB is much more powerful than that. VB Capabilities.
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Intermediate Visual Basic CISP 371 CRC Prof. Chapman
VB Capabilities • Most people think that Visual Basic is only useful if you want to build a GUI program that runs on a desktop PC. • But VB is much more powerful than that. CISP 371 Chapman
VB Capabilities • VB can be used to work with databases and to build web sites. • Who needs Java or Javascript or PHP? Who needs SQL or Oracle or MySQL? Not a master VB programmer. CISP 371 Chapman
VB Capabilities • VB can handle • Windows desktop GUI applications • Windows web applications • Database connectivity • Extension of the language • OOP • Application security CISP 371 Chapman
Windows Desktop GUI Apps • This was covered in the prerequisite course CISP 370. • More to come about what I expect you all to know in this area. CISP 371 Chapman
Language Extension • The rest of what VB can do can is defined within the huge class library called the .NET Framework. • As the first part of this course we’ll work with this library. CISP 371 Chapman
OOP • You will learn how to effectively use the .NET Framework. You will also extend the .NET Framework into customized classes using the OOP concepts of inheritance, polymorphism, and encapsulation. • These concepts are vital when programming VB web apps and database connectivity. CISP 371 Chapman
OOP • You will be able to create advanced memory storage for your program’s data. • You’ll learn to communicate between modules with events and exceptions, to organize data and procedures into classes, to create expandable array-like objects called collections, and to save organized data to a file using serialization. CISP 371 Chapman
Database Connectivity • The subset of the .NET Framework that deals with connecting an app to a database is called ADO.NET. • These classes let you use a database as a permanent storage area for your application’s data. CISP 371 Chapman
Database Connectivity • You can use VB to copy databases into memory, search the data with VB, edit the data, and save the data back to the database. • Working with an existing database with VB does not require SQL. CISP 371 Chapman
Windows Web Applications • The subset of the .NET Framework that deals with connecting an app to a database is called ASP.NET. • These classes let you create an event-driven web page that contains controls. CISP 371 Chapman
Windows Web Applications • You can use VB to build web sites using the same techniques as building desktop applications. CISP 371 Chapman
What You Already Know • This is contained on Blackboard in the document “CISP 370 topics”. • If you don’t feel comfortable with any of these topics, plan to meet with me ASAP during office hours for a quick tutorial. CISP 371 Chapman
What You Already Know • Let’s look at two examples • TextBox input data validation • Complicated multiple-window WinApp to play craps CISP 371 Chapman
Simple CISP 370 WinApp • This WinApp accepts input in the TextBox and then validates the input as a positive integer. If input is invalid, then a MessageBox dialog informs the user. CISP 371 Chapman
Simple CISP 370 WinApp • Read the code behind MainForm to see the • btnProcess_Click() event handler definition • the validation technique using Val() and an If statement CISP 371 Chapman
More Complicated WinApp • In the past, the last homework in my CISP 370 asked for a WinApp with three windows that played the game of craps. • The user could place bets and enable a log file to keep track of their bets. • The application would determine whether a bet had won or lost and update the user’s bankroll. CISP 371 Chapman
More Complicated WinApp • “GUI sketches” are a method to design the application before writing a single line of VB.NET code. • In these sketches the developer communicates their vision for the abilities of each window. CISP 371 Chapman
sketch of window control names what user can do in window CISP 371 Chapman
More Complicated WinApp • After the windows have been sketched out, then the developer writes the code behind each window. CISP 371 Chapman
More Complicated WinApp • The main window is always on the screen and is where the user rolled the dice and managed the game. The user can navigate to the other windows and exit the app here. CISP 371 Chapman
More Complicated WinApp • The bets window allows the user to place a bet prior to their next roll. The allowable bets depend on the current state of the game (has the point been set?), the table minimum bet, and the total amount of money the user has. CISP 371 Chapman
More Complicated WinApp • The show-all-bets window displays the currently placed bets and their amount. CISP 371 Chapman
What You Don’t Yet Know • How to use .NET Framework classes directly (instead of having Visual Studio automatically generate the necessary code). • How to build customized classes that are based upon the .NET Framework. • How to group code together into a coherent class that other programmers would find useful. CISP 371 Chapman
What You Don’t Yet Know • How to connect your app to a database using the ADO.NET library. • How to build active web pages using .NET techniques and the ASP.NET library. CISP 371 Chapman
My Goal • Students who finish this course have enough knowledge about using and expanding the .NET Framework library to do whatever they like with Visual Basic. • VB – it’s not just for desktop applications any more! CISP 371 Chapman