VBScript Reference Manual for InduSoft Web Studio

VBScript Reference Manual InduSoft Web Studio
VBScript Naming Rules and Conventions
VBScript has some simple standard rules that apply to all VBScript variable names. These are:
• Must begin with an alpha character (A...Z)
• After the first character, they can contain letters, digits and underscores. No other embedded
characters are permissible.
• Must be less than 255 characters in length
• Must be unique in the scope in which they are declared
• Cannot use names that are Keywords
Permissible Not permissible
a class.item
b2 +a
c_34_ @Test123
Microsoft recommends following a naming convention for variables, based on their data type. The
variable name would contain a prefix, signifying its data type. Microsoft used the vb prefix for VBScript
defined constants, and it is recommended to avoid using these prefixes with variables. The Microsoft
recommended prefixes for programmer defined variables and constants are:
Microsoft Suggested Naming Convention for Variables
Data Subtype Prefix Example
Boolean bln blnFound
Byte byt bytRasterData
Currency cur curTotal
Date/Time dtm dtmStart
Double dbl dblTolerance
Error err errOrderNum
Integer int intQuantity
Long lng lngDistance
Object obj objCurrent
Single sng sngAverage
String str strFirstName
Variant Var varNumber
The Microsoft suggested naming convention are part of the “Hungarian Notation Standard” prefixes,
developed by Microsoft in 1972. Although many of the other prefixes are for C++ programmers, there
are a couple other Hungarian Notation prefixes that might be useful:
Additional Hungarian Notation Prefixes
Use Prefix Example
Pointer p pIndex
Class c cObject
Float f fCalc
Nested Class X X
Key Notes:
• Good programming would suggest that variable names are descriptive
• While VBScript variable names are not case sensitive, the name of an ActiveX control
inserted by IWS is case sensitive when referenced from a VBScript code segment.
• Most VBScript naming rules can be overridden by enclosing the name in brackets. For
example, [@a.1] would be a valid VBScript name.
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