1. Visual Basic.Net Seminar June 7, 2004

2. Topics Today include  The.Net Framework  Studio.Net Environment  VB.Net  Introduction to VB.Net  Loops and Control Structures

3. The.Net Framework What is the.Net Framework What is the.Net Framework Common Language Runtime Common Language Runtime.Net Managed Assemblies.Net Managed Assemblies Compilation of.Net Code Compilation of.Net Code.Net Framework Class Library.Net Framework Class Library.Net Languages.Net Languages The future of.Net The future of.Net

4. What is the.Net Framework Primarily a development platform (mostly effects application development) Primarily a development platform (mostly effects application development) Consists of two main parts Consists of two main parts –Common Language Runtime –.Net Framework Class Library

5. CLR (Common Language Runtime) Provides a “runtime environment” for the execution of code written in ANY.Net Language Provides a “runtime environment” for the execution of code written in ANY.Net Language “Manages” “Manages” –The overall execution of.Net code –Inheritance, Memory, Debugging, and application development across Multiple languages

6. CLR (Continued) Languages that utilizes the.Net framework must follow the CLS Languages that utilizes the.Net framework must follow the CLS –Common Language Specification –Outlines the rules and standards required or needed by the CLR to execute.Net code. The CLR will execute Managed Assemblies The CLR will execute Managed Assemblies Intermediate Languages managed by the CLR are called Managed Code Intermediate Languages managed by the CLR are called Managed Code The CLR will manage for the IL The CLR will manage for the IL –Garbage collection –Object instantiation –Memory allocation Components written in Managed Code by the CLR are called.Net Managed assemblies Components written in Managed Code by the CLR are called.Net Managed assemblies

7. .Net Managed Assemblies Basic Unit of deployment of.Net Applications Basic Unit of deployment of.Net Applications Similar to the Microsoft COM Objects Similar to the Microsoft COM Objects Each Managed Assembly contains a Manifest Each Managed Assembly contains a Manifest –Hold definitions of other components required for execution of the application –Prevents the problems associated with conflicting DLL’s –Revision numbers and components are listed in the manifest –Two versions of the same DLL can then co-exist

8. Compilation of.Net code All.Net languages are first compiled into an intermediate language called MSIL or IL (Microsoft Intermediate Language) All.Net languages are first compiled into an intermediate language called MSIL or IL (Microsoft Intermediate Language) The MSIL is then “Just In Time” (JIT) compiled at first execution of the code and managed by the CLR The MSIL is then “Just In Time” (JIT) compiled at first execution of the code and managed by the CLR All MSIL or IL code can be compiled directly to native code with the following All MSIL or IL code can be compiled directly to native code with the following –Compiling native code will provide faster startup execution of the code –Performance during execution of the code will then be sacrificed –During JIT Optimization is placed on the Managed Code in order to improve performance at the time of execution

9. .Net Framework Class Library Provide a library of base classes that developers can use in their own applications written in ANY.Net language Because of the use of these base classes, Inheritance can then be extensively used in languages that use the.Net Framework

10. .Net Languages.Net applications can be written by any or a combination of many.Net languages.Net applications can be written by any or a combination of many.Net languages Languages include Languages include –VB.Net –C# –J# –Managed C++ (default in studio is set for managed C++) Applications can be developed without the use of Studio.Net Applications can be developed without the use of Studio.Net –Applications can be developed still using a simple text editor –ASP.Net Applications as well as other apps can be still developed using notepad

11. The future of the.Net Framework Standards were release in 2000 from Microsoft to the community Standards were release in 2000 from Microsoft to the community GNU.Net is a project in the Linux community that is presently developing a CLR to run in the Linux environment GNU.Net is a project in the Linux community that is presently developing a CLR to run in the Linux environment Languages planned to include the CLS are Languages planned to include the CLS are –APL –COBOL –Eifel –Fortran –Haskel –Mercury –Mondrian –Oberon –Pascal –Perl –Python –RPG –Scheme

12. Studio.Net Environment The IDE Studio.Net Studio.Net The Start Page The Start Page Problems with Studio.Net in the lab environment Problems with Studio.Net in the lab environment

13. Studio.Net All present.Net languages are included under one development environment All present.Net languages are included under one development environment –When using any one of the languages, the studio must be used (there is no longer an environment for each language) –You have to start a new solution/project Projects are containers that contain the files associated with a particular project Projects are containers that contain the files associated with a particular project A solution is a container that contains one or more projects or project containers A solution is a container that contains one or more projects or project containers When the IDE is started you have the Projects tab, online resources, and My Profile When the IDE is started you have the Projects tab, online resources, and My Profile

14. The Start Page Previous Projects Tab for this view Tab for Additional Help Profile and environment settings Start a new project Open a project in a diff. location

15. Problems with Studio.Net environment in the lab.Net security must allow access to the J: drive or the local intra net in order to work properly.Net security must allow access to the J: drive or the local intra net in order to work properly Problems arise when debugging apps on an ASP.Net server that is not part of the current domain (CLC) Basic apps will still work fine Problems arise when debugging apps on an ASP.Net server that is not part of the current domain (CLC) Basic apps will still work fine These problems are not present if IIS and remote debugging tools are installed on the client machine These problems are not present if IIS and remote debugging tools are installed on the client machine –This solution is fine for students but is not practical for a lab –Due to security holes of IIS you can have hundreds of security risks on a given network. –In the Real world situation, all apps will be placed on a server anyway

16. Visual Basic.Net General Features General Features Additional Features of VB.Net Additional Features of VB.Net What has changed in VB.Net What has changed in VB.Net

17. General features It is an object oriented language It is an object oriented language –Students do better with this subject when they have a firm understanding of objects –In the past VB had objects but focus was not placed on them –VB.Net use objects and inheritance with everything Uses exception handling extensively Uses exception handling extensively –New techniques are shown to the student for providing feedback from their programs in order to help trouble shoot errors –Like with most OOP languages, exceptions that are not handled will cause programs to abnormally end or exit Uses “generics” with creating classes and Sub programs Uses “generics” with creating classes and Sub programs –Can use the top data type on inheritance of type Object –Used for late binding of data types and is quite useful when implementing stacks or queues of any data type (.Net 2.0) Provides a quick way to develop heavy duty applications in a windowing environment Provides a quick way to develop heavy duty applications in a windowing environment It is a useful tool for developing event driven programs It is a useful tool for developing event driven programs

18. Additional Feature of VB.Net Can create both windows applications and web applications at the click of a mouse button The interface between the Databases and applications –A–A–A–Are the same between web apps and windows apps –A–A–A–All data are transferred between the apps in XML format regardless if it is a web application or a windows application –A–A–A–A copy of the data from the database is loaded into a data set. –P–P–P–Persistent connections between the application and the database no longer exists Every form is a class and new forms now have to be instantiated VB.Net is still not case sensitive

19. What is Not in VB.Net Data Controls –B–B–B–Because of the different way that the apps connect to the database, there is no longer the support of data controls in VB.Net –P–P–P–Persistent connections with the database is no longer present Object instantiation is now done differently Garbage collection for references that lose there objects are done periodically not when the reference lose its scope Periodic changes throughout the language making it vastly different from VB 6.0 in order to make it compliant to the.Net Framework and the CLS

20. The Introduction to VB.Net Data Types in VB.Net Data Types in VB.Net Functions and Sub Procedures Functions and Sub Procedures Practice Examples Practice Examples

21. Data Types in VB.Net Data Types and possible values Data Types and possible values –Integer -> -2,147,483,648 (4 bytes) –Double -> floating point numbers with 14 digits of accuracy (8 Bytes) –Decimal -> decimal values ( 16 bytes replaced currency in 6.0) –Date -> the date (8 Bytes) –Byte -> 0 to 255 (1 Byte) –Char -> Unicode character (2 Bytes) –Boolean ->True or false value (2 Bytes) –Single -> floating point number with 6 digits of accuracy (4 bytes) –Short -> 2 byte integer –Long -> 8 byte integer –String -> an arrangement of alpha-numeric characters varies in length –Object -> any data type 4 bytes

22. Functions and Sub procedures / Programs in VB.Net (Methods) Functions and sub procedures must either have a sub or function keyword in the function or sub procedure heading Functions and sub procedures must either have a sub or function keyword in the function or sub procedure heading They can be either public or private (following the same conventions in OOP languages such as C++ or Java) They can be either public or private (following the same conventions in OOP languages such as C++ or Java) All parameters are passed by value by default in VB.Net All parameters are passed by value by default in VB.Net Parameters of any data type may be passed by reference Parameters of any data type may be passed by reference All Objects and arrays are passed by reference not value All Objects and arrays are passed by reference not value All events are handled by a sub procedure in VB.Net All events are handled by a sub procedure in VB.Net Functions return a value and Sub Procedures do Not Functions return a value and Sub Procedures do Not

23. Practice example 1 You can use the text book given to you to get the basics needed in programming VB starting on page 477 You can use the text book given to you to get the basics needed in programming VB starting on page 477 Getting familiar with VB.Net Getting familiar with VB.Net –Write a program that will take text from one text box and place that text in another text box with a click of a button –Take a look at the attributes of each control A control can be a button text box etc. A control can be a button text box etc. Each control should contain names that follow VB specifications i.e. txtBox1 txtBox2 btnMove Each control should contain names that follow VB specifications i.e. txtBox1 txtBox2 btnMove Each name as always should be meaningfull Each name as always should be meaningfull

24. Practice Example 2 Using Functions in VB.Net Using Functions in VB.Net –Use the text boxes from the previous example –Add a text box –Provide a function that adds the values of text box 1 and text box 2 –Place the answer in text box3 –Use variables of type double and use the CDbl() function to convert the string value of the text box to a double page 485 in your text

25. Loops and control structures The If Statement The If Statement The Select Case Statement The Select Case Statement The Do While and Loop While loops The Do While and Loop While loops The For Loop The For Loop

26. The IF Statement Every If statement must contain a then and an end if Example: –I–I–I–If Num1 < 2 Then MessageBox.show(“The value is less than 2”) End If –I–I–I–If Num1 <> 4 then MessageBox.Show(“The value is not 4”) End If The relational operators that can be used in VB are –>–>–>–> –<–<–<–< –=–=–=–= –>–>–>–>= –<–<–<–<= –<–<–<–<> (Not equal to)

27. The Select Case statement The select case statement is a lot like the switch statement in Java The select case statement is a lot like the switch statement in Java It can use ANY data type in VB It can use ANY data type in VB Example Example Select Case Num1 Case 1 DoSomeThing() Case 2 Do SomethingElse() End Select Yes you can use strings as well Yes you can use strings as well

28. Do While Loops Do while loops evaluate the expression first then executes the Loop Body Do while loops evaluate the expression first then executes the Loop Body Act much in the same as All While loops in languages like C++ and Java Act much in the same as All While loops in languages like C++ and Java Example Example Do While Num1 < 10 Num1 += 1 Loop

29. Loop While Loops The Body of the Loop is executed first then the expression is evaluated The Body of the Loop is executed first then the expression is evaluated The loop will execute at least once The loop will execute at least once This is a lot like the do while loop in Java and students get confused with this subtle change This is a lot like the do while loop in Java and students get confused with this subtle change Example ExampleDo Num1 += 1 Loop While Num1 < 10

30. End Of Day 1

31. VB.Net Seminar Day 2 June 8, 2004

32. Microsoft SQL Server  MS SQL Basics  The Enterprise Manager  Creating Databases  Connecting to Databases  The use of the Data Set  Exception Handling

33. Microsoft SQL Basics Differences between MS SQL and Access Differences between MS SQL and Access Advantages of MS SQL Advantages of MS SQL Quirky things with SQL Quirky things with SQL Connecting to the database with the manager Connecting to the database with the manager

34. Differences between MS SQL and Access SQL More Powerful than MS Access SQL More Powerful than MS Access –Larger data types are available –Connection over a network provide access to multiple clients –Blob data type available A client is required to connect to the SQL Database A client is required to connect to the SQL Database

35. Advantages of MS SQL Can handle multiple users at one time Can handle multiple users at one time Ideal for web sites and web applications Ideal for web sites and web applications Contain the BLOB (Binary Large Object) which enables a user to store images in a database Contain the BLOB (Binary Large Object) which enables a user to store images in a database Larger numeric values can be stored in each field Larger numeric values can be stored in each field

36. Quirky problems with SQL No Auto Number Data Type in MS SQL No Auto Number Data Type in MS SQL Auto number is an integer data type Auto number is an integer data type Identity is set to yes Identity is set to yes And the seed is set to one And the seed is set to one This gives you the option to set the starting number and the increment you want the auto number to have This gives you the option to set the starting number and the increment you want the auto number to have

37. Enterprise Manager Connecting to the database Connecting to the database Getting through the confusion of locating databases Getting through the confusion of locating databases Defining the different containers in the Manager Defining the different containers in the Manager

38. Connecting to the DBMS Start the Enterprise Manager Start the Enterprise Manager Right Click SQL Server group Right Click SQL Server group

39. Connecting to the DBMS Click on SQL Server Registration Click on SQL Server Registration Click next Click next In the text box labeled Available Servers type Sigma.vbnet.matcm p.ncc.edu In the text box labeled Available Servers type Sigma.vbnet.matcm p.ncc.edu Click Add then next Click Add then next

40. Connecting to the DBMS Click on SQL Server login Click on SQL Server login Username is the first six letters of your last name and your first initial Username is the first six letters of your last name and your first initial Password is vbnet Password is vbnet Click next and click next again Click next and click next again Click Finish Click Finish Click close on the next dialog box Click close on the next dialog box

41. Getting through the concussion MS SQL Enterprise Manager will display ALL of the databases located on the server MS SQL Enterprise Manager will display ALL of the databases located on the server Access to each database is controlled by the DBMS Access to each database is controlled by the DBMS ALL tables are displayed in each database ALL tables are displayed in each database This includes tables that are used by the DBMS This includes tables that are used by the DBMS

42. The Containers in SQL Each container has a specific role Each container has a specific role Student Databases are in the databases container Student Databases are in the databases container

43. Database Container Every students database is displayed Every students database is displayed Only the database that the student has permissions for can be opened Only the database that the student has permissions for can be opened Click on the database container with your username Click on the database container with your username

44. Student Database container

45. Creating the Database Creating tables Creating tables Properties of the data types Properties of the data types Entering and Displaying Data in database Tables Entering and Displaying Data in database Tables

46. Creating Tables Right click on the table container Right click on the table container Click new table Click new table This is a lot like the Access interface with different data types. This is a lot like the Access interface with different data types. At this points explore the interface and notice the differences At this points explore the interface and notice the differences

47. Properties of Data Fields Each Data Field has a length property Each Data Field has a length property This sometimes causes a problem with students who make this field too small This sometimes causes a problem with students who make this field too small Each data Field can also allow null values Each data Field can also allow null values After defining each column and setting all the properties set the primary key by right clicking on the field that is to be the key After defining each column and setting all the properties set the primary key by right clicking on the field that is to be the key

48. Entering and Displaying Data Right Click the table Right Click the table Click Open Table Click Open Table Click Return All Rows Click Return All Rows From here you can view and enter new data into the table From here you can view and enter new data into the table

49. Practice Example 1 Creating a Table in VB.Net Creating a Table in VB.Net Create a table of customers in a hardware store Create a table of customers in a hardware store Columns will include Columns will include –Customer ID –First Name –Last Name –Address –Zip Code Fill the table with data Fill the table with data Display that data Display that data

50. Connecting to the database with VB.Net Applications The Data Provider The Data Provider The Data Set The Data Set The use of the wizard The use of the wizard

51. The Data Adapter Needed to connect to every DBMS Needed to connect to every DBMS Must Use the Adapter that represents the DBMS you are going to use Must Use the Adapter that represents the DBMS you are going to use We are going to use the SQLDataAdapter Object We are going to use the SQLDataAdapter Object Holds the information on how to Holds the information on how to

52. The Data Provider Manipulates data through the use of SQL statements or commands Manipulates data through the use of SQL statements or commands Hold connection information to the Database Hold connection information to the Database Contain two Major components Contain two Major components –Data Adapter Object – updates data in the dataset –Connection Object – maintains the connection

53. The Data Set Holds data returned from a procedure or Query performed by the data adapter Holds data returned from a procedure or Query performed by the data adapter Provides a local “Copy” of the data from the table on the local machine Provides a local “Copy” of the data from the table on the local machine Prevents persistent connections with the database and reduces network traffic Prevents persistent connections with the database and reduces network traffic

54. The use of the wizard Give Demo on using the wizard Give Demo on using the wizard

55. The Data Set Generating the data set object Generating the data set object The use of the onload event handler The use of the onload event handler Binding controls Binding controls Creating navigation for a database Creating navigation for a database

56. Generating the Data Set Object Once the Data Adapter and the connection object is created click on Data in the menu Once the Data Adapter and the connection object is created click on Data in the menu Click generate dataset Click generate dataset Give a name to the dataset Give a name to the dataset Click OK Click OK

57. The use of the onLoad event Handler Double click the form Double click the form Place the fill method in the Load event handler Place the fill method in the Load event handler This will fill the dataset object with the data from the table when the form loads This will fill the dataset object with the data from the table when the form loads Example ExampleSQLDataAdapter1.Fill(MyDataSet1)

58. Binding Controls Once you create a data set you can then bind the controls of the form to fields or columns of the database table Once you create a data set you can then bind the controls of the form to fields or columns of the database table This is done with in the Bindings property in the text box properties sheet This is done with in the Bindings property in the text box properties sheet Under the bindings property click text and then the field you wish to bind to the text box Under the bindings property click text and then the field you wish to bind to the text box

59. Creating navigation for a database Managed by the BindingManagerBase Object Managed by the BindingManagerBase Object This object contains the Position Property the holds the current position of the record in the dataset This object contains the Position Property the holds the current position of the record in the dataset This is done by adding one to the position attribute of the object This is done by adding one to the position attribute of the object Methods of this object includes Methods of this object includes –Addnew() –EndCurrentEdit() –CancelCurrentEdit() -> provides a role back feature –RemoveAt() -> deletes current row at given position

60. Exception Handling Implementation Use try catch block much the same in Java Use try catch block much the same in Java Can help trouble shoot connections to databases Can help trouble shoot connections to databases Very important to use when filling the dataset Very important to use when filling the dataset Example ExampleTry SqlDataAdapter1.Fill(DataSet11) SqlDataAdapter1.Fill(DataSet11) Catch ex As Exception MessageBox.Show("Error will dataset fill") MessageBox.Show("Error will dataset fill") End Try

61. Practice Example 2 Connecting a form to your Hardware customers Connecting a form to your Hardware customers Create a form with text fields for each column Create a form with text fields for each column –Create the data Adapter and Data Connection with the use of the wizard –Create the data set object –Create the onload event handler to fill the data set –Bind your controls –Be sure to use exception handling for filling the data set –Create a Next button to navigate to the next record in the database

62. End Of Day 2

63. VB.Net Seminar Day 3 June 9, 2004

64. Topics  Adding and Editing Records  Updates and deletes with Bound controls  Classes and Modules in VB.Net  Menus  From design  MDI (Multi Document Interfaces)  Bound and unbound controls in VB.net  Why Unbound controls are used

65. Adding and Editing Records When Adding records When Adding records –The Position of the dataset should be set to the end –The text boxes should be cleared The AddNew() Method accomplishes all this in one method call The AddNew() Method accomplishes all this in one method call The AddNew() Method is part of the BindingManagerBase Object The AddNew() Method is part of the BindingManagerBase Object When changes are being made, a cancel button should be provided to “Roll Back” changes made to the data set When changes are being made, a cancel button should be provided to “Roll Back” changes made to the data set

66. Edit When Navigating the database the Text boxes should be disabled to prevent changes When Navigating the database the Text boxes should be disabled to prevent changes There should be an edit button that There should be an edit button that –Disables the navigation button –Enables the text boxes for editing –Provide a cancel button that “Roles Back” the changes that are made by calling the CancelCurrentEdit() method of the BindingManagerBase Object

67. Update and Deleting Records This is done by This is done by –Ending the current edit by calling EndCurrentEdit() in the BindingManagerBase class –Updating the DB with Update() in the data adapter –Cause the dataset to reflect the changes by calling the AcceptChanges() method in the data set Deleting the records Deleting the records –First Ask the user if they are sure they want to delete –Use the RemoveAt() method of the BindingManagerBase object –Update the database with the Update() method –Have the dataset reflect the change by calling the AcceptChanges() method of the dataset object

68. Practice Example 1 With the Example finished yesterday With the Example finished yesterday –Add an Add Button –Add an Edit Button –Provide a Save and a delete feature –Use exception handling for everything

69. Classes and Modules in VB.Net Creating classes in VB.Net Creating classes in VB.Net The constructor and Sub procedures in VB.Net The constructor and Sub procedures in VB.Net The use of Modules The use of Modules

70. Creating Classes in VB.Net Classes can be added to a project by Classes can be added to a project by –Right clicking the project container –Click add –Click add class As in Most OOP Languages VB classes have As in Most OOP Languages VB classes have –Public and private attributes –Public and private Methods (called functions or sub procedures) –Constructors and Destructors (destructors are not really needed in VB because of garbage collection)

71. Modules Modules can also be added to a project to provide a place for “Global” Methods and Identifiers Modules can also be added to a project to provide a place for “Global” Methods and Identifiers These Identifiers and methods can be either public or private These Identifiers and methods can be either public or private Public Identifiers and methods can be accessed from all of the forms and classes in the VB project Public Identifiers and methods can be accessed from all of the forms and classes in the VB project

72. Practice Example For this Example For this Example –Create an Auto Class –An Auto will have Three Attributes Three Attributes Three Methods Three Methods Two constructors Two constructors –Try instantiating the method in the form

73. Menus When adding menus to a form you can type in the choice right into the menu object When adding menus to a form you can type in the choice right into the menu object Click event handlers can then be added for each menu choice in the same manner as the button Click event handlers can then be added for each menu choice in the same manner as the button

74. Form Design Colors are important Colors are important –They should be contrast in color –Ease to read –Easy on the eyes for long periods of viewing Should provide easy navigation Should provide easy navigation Should provide a way to enter the data easily with just using the keyboard Should provide a way to enter the data easily with just using the keyboard

75. Multi Document Interfaces (MDI) When creating a form in VB.Net you are creating a class When creating a form in VB.Net you are creating a class Every class in vb must be instantiated before it is used Every class in vb must be instantiated before it is used This is accomplished by using the new keyword This is accomplished by using the new keyword When the instance of the form is created, the form can then be visible by calling the forms show method When the instance of the form is created, the form can then be visible by calling the forms show method Closing a form does not exit the program. To exit the program the End method should be called Closing a form does not exit the program. To exit the program the End method should be called

76. Practice Example 3 Create a Form that will be a switch board Create a Form that will be a switch board –Add a form to yesterdays example –Place a button that will open the customer form –Place a button that will exit the program

77. Bound and Unbound Controls So far we have seen the benefits of bound controls So far we have seen the benefits of bound controls These are ok if you intend to use the same SQL query for the whole application These are ok if you intend to use the same SQL query for the whole application Once controls are bound to a data set, changes to the query in the data adapter can not be accomplished Once controls are bound to a data set, changes to the query in the data adapter can not be accomplished Unbounded controls give you the power to create new data adapters with new queries. Unbounded controls give you the power to create new data adapters with new queries. Values can then be placed into the query to find specific records in a database Values can then be placed into the query to find specific records in a database

78. End Day 3

79. VB.Net Seminar Day 4 June 10, 2004

80. Topics  ASP.Net basic applications  ASP.Net Database applications  Web Forms  Crystal Reports  Creating Help Files  Demo with Serial port programming and VB.Net  Handout Certificates

81. ASP.Net basic Applications

85. End Day 4