Phonetics Sensaphone SCADA 3000, User Manual

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Usage
Dim varname[([subscripts])][, varname[([subscripts])]] . . .
Arguments
varname
Name of the variable; follows standard variable naming conventions.
subscripts
Dimensions of an array variable; up to 60 multiple dimensions may be declared.
The subscripts argument uses the following syntax:
upperbound [,upperbound] . . .
The lower bound of an array is always zero.
variable name definitions
A named storage location that can contain data that can be modified during program execution.
Each variable has a name that uniquely identifies it within its level of scope.
Variable names:
• Must begin with an alphabetic character.
• Can’t contain an embedded period or type-declaration character.
• Must be unique within the same scope.
• Must be no longer than 255 characters.
If...Then...else Statement
Conditionally executes a group of statements, depending on the value of an expression.
If condition Then statements [Else elsestatements ]
Or, you can use the block form syntax:
If condition Then
[statements]
[ElseIf condition-n Then
[elseifstatements]] . . .
[Else
[elsestatements]]
End If
Arguments
condition
One or more of the following two types of expressions:
A numeric or string expression that evaluates to
True or False . If condition is
Null, condition is treated as False .
An expression of the form TypeOf objectname Is objecttype . The objectname is any
object reference and objecttype is any valid object type. The expression is True if
objectname is of the object type specified by objecttype ; otherwise it is
False
.
statements
One or more statements separated by colons; executed if condition is
True
.
22-7
Chapter 22: Distributed Control using Visual Basic