DISPLAYING ON THE SCREEN

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DISPLAYING ON THE SCREEN
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THREE WAYS

• SIMPLE HTML CODE
• THE ASP FORMAT
• HTML WITH VB EMBEDDED
• THE ASP.NET FORMAT

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SIMPLE HTML CODE
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ASP FORMAT
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ASPNET STRUCTURE

• SCRIPT TAGS
• INDICATE LANGUAGE
• MANY LANGUAGES POSSIBLE
• VB, JAVA, C
• RUNAT
• THE CODE IS BEING RUN ON THE SERVER
• SCRIPT TAG MUST BE CLOSED
• lt/SCRIPTgt

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• SUB PAGE_LOAD ( )
• THIS IS EXECUTED FIRST
• NEEDS
• END SUB

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SEQUENCE

• (p.57) Whenever ASP.NET loads up a page, it
  executes any code contained within the Page_Load(
  ) subroutine first.
• The web server scans the file to see if there is
  a ltscript runat servergt tag. If there, it is
  processed first.

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SOME EXAMPLES IN SEQUENCING
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DECLARATIONS

• (p.92)DIM
• NAME OF VARIABLE IS ESTABLISHED
• SPACE ALLOCATED IN MEMORY
• UNTIL VALUE ASSIGNED, VARIABLE CONTAINS NOTHING
• USE VB FUNCTION
• ISNOTHING (VARNAME) TO CHECK IF VARIABLE HAS
  VALUE
• WILL RETURN TRUE OR FALSE, NOT VALUE

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NAMING A VARIABLE

• (p. 92)
• RULES FOR NAMING A VARIABLE
• MUST BEGIN WITH LETTER (NOT NUMBER OF SYMBOL)
• MAY NOT CONTAIN EMBEDDED PERIOD OR SPACE
• CANNOT USE VB.NET KEYWORDS (RESERVED WORDS)

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• Dim strStudentName as String
• Dim strStName, strStStatus as String
• Dim strStName as String Joe

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DATA TYPES (p. 95)

• Numeric
• Integer (whole numbers only)
• Byte (0 to 255)
• Short (/- 32768)
• Long (/- 9 x 1019)
• Single (floating point numbers)
• Double
• Decimal
• String
• Char
• Date
• Boolean

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VARIABLE NAMING CONVENTIONS

• P. 99 and 100
• blnMember
• BytDaysInMonth
• CharWang
• datDateOfBirth
• intAge
• strNameFirst