programming-for-dummies

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Creating Comments
Creating Comments
Visual Basic lets you create comment lines with the apostrophe (‘) or REM
keyword, such as
‘ The apostrophe defines a line comment
PRINT “This is a simple BASIC program”
REM The REM (Remark) keyword is another way
REM to create a comment
END ‘ This is the end of the program
REALbasic uses both the apostrophe and the REM keyword along with the
double slash characters (//), such as
PRINT “This is a simple BASIC program”
END // This is the end of the program
Declaring Variables
In early versions of BASIC, you could create a variable any time you needed
it. However as BASIC adopted structured programming techniques, more
modern dialects of BASIC (such as Visual Basic and REALbasic) now force
programmers to declare variables by defining the variable name and data
type. A typical variable declaration looks like this:
Dim VariableName As DataType
VariableName can be any descriptive name, such as SalesTax, Players_
on_Team, or MoneyEmbezzled. The data type defines the type of data the
variable can hold and the amount of data the variable can hold. You can also
declare multiple variables on a single line, such as
Dim VariableName1, VariableName2, VariableName3 As DataType
Declaring string data types
Strings represent text, such as a single character (“A”) or several words
(“This is a string of text”). To declare a string variable, use the
String keyword, such as
Dim FirstName As String
In Visual Basic (but not in REALbasic), you can also declare a variable as a
Char data type, which can only hold a single character, such as the letter
“H.” To declare a Char data type, use the Char keyword, such as
Dim Grade As Char