Visual basic

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Visual basic

• The basics

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What is it?

• A programming language
• Create programs to run on windows machines
• Once program (.exe) is created,should work on
  any windows machine (even is visual basic is not
  installed)
• Programs can be anything calculate groundwater
  levels, games, or even a virus

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Graphical interface

• Design interface to program (drag and drop)
• Add code to interact with interface
• Compile
• Fix bugs
• Run

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Options for graphical interface

• Whole list of options
• Select object that you want
• Draw on form
• Modify controls at right side (caption, name, etc)

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The code

• Write code controlled by each item
• Usually, object oriented
• Program flow controlled by user, not necessarily
  sequential

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Mathematical operations
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Other operators
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variables

• Should be declared
• Dim total as integer
• Dim myName as string
• If not declared, VB automatically declares it
  using a default
• byte (0-255),integer (-32,768 to 32,767),single
  (-3.2E38 to 3.4E38)
• long,double,currency, and decimal
• String (characters), date and boolean
• Must be less than 255 characters, no spaces, and
  cannot begin with a number.

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objects

• An embedded object
• Has attributes
• Radius.text

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statements

• If .thenelse
• If z.Text x.Text y.Text  Then
  display.Caption "Correct" Image2.Visible
  "true" Line1.Visible "true" Else
  display.Caption "Wrong" Image2.Visible
  "false" Line1.Visible "false" End If

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loops

• Do while
• Do while counter lt1000
•              num.Textcounter
•              counter counter1
•  Loop
• For..Next
• For  counter1 to 10
•              display.Textcounter
• Next

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Okaynow how do you do it?

• Start visual basic
• Click on standard.exe
• Double-click on form
• Make it look like this
• Run, compile

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Adding an interface

• Draw interface
• Set properties
• Write event code

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Compile and run

• May show bugs

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Can save as executable

• Under file, save as exe
• This file can be transferred elsewhere and run.

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components

• Hit cntrl-T
• A wide variety of possible controls to add
• Quicktime, for example
• We chose Microsoft Common Dialog Control

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Open a file and play it

• Private Declare Function sndPlaySound Lib
  "winmm.dll" Alias "sndPlaySoundA" (ByVal
  lpszSoundName As String, ByVal uFlags As Long) As
  Long
• Private Sub Command1_Click()
• ' declare the file name as string variable
• Dim FileName As String
• 'This allows us to access a WIN32 function in VB.
• ' now open the dialog box
• CommonDialog1.Filter "Wav files (.wav)"
• CommonDialog1.FilterIndex 1
• CommonDialog1.ShowOpen
• 'now set the file name to whatever you picked
• FileName CommonDialog1.FileName
• 'play it
• sndPlaySound FileName, SND_ASYNC
• End Sub

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More weird stuff

• Do a cntr-T and add Microsoft Direct
  text-to-speech
• Now you should see a pair of lips
• Add a text box and another button and
• Private Sub Command2_Click()
• DirectSS1.Speak Text1.Text
• End Sub