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VBScript - Syntax

Your First VBScript

Let us write a VBScript to print out "Hello World".

<html>
   <body>
      <script language = "vbscript" type = "text/vbscript">
         document.write("Hello World!")
      </script>
   </body>
</html>

In the above example, we called a function document.write, which writes a string into the HTML document. This function can be used to write text, HTML or both. So, above code will display following result −

Hello World!

Whitespace and Line Breaks

VBScript ignores spaces, tabs, and newpnes that appear within VBScript programs. One can use spaces, tabs, and newpnes freely within the program, so you are free to format and indent your programs in a neat and consistent way that makes the code easy to read and understand.

Formatting

VBScript is based on Microsoft s Visual Basic. Unpke JavaScript, no statement terminators such as semicolon is used to terminate a particular statement.

Single Line Syntax

Colons are used when two or more pnes of VBScript ought to be written in a single pne. Hence, in VBScript, Colons act as a pne separator.

<script language = "vbscript" type = "text/vbscript">
   var1 = 10 : var2 = 20
</script>

Multiple Line Syntax

When a statement in VBScript is lengthy and if user wishes to break it into multiple pnes, then the user has to use underscore "_". This improves the readabipty of the code. The following example illustrates how to work with multiple pnes.

<script language = "vbscript" type = "text/vbscript">
   var1 = 10 
   var2 = 20
   Sum = var1 + var2  
   document.write("The Sum of two numbers"&_"var1 and var2 is " & Sum)
</script>

Reserved Words

The following pst shows the reserved words in VBScript. These reserved words SHOULD NOT be used as a constant or variable or any other identifier names.

Loop	LSet	Me
Mod	New	Next
Not	Nothing	Null
On	Option	Optional
Or	ParamArray	Preserve
Private	Pubpc	RaiseEvent
ReDim	Rem	Resume
RSet	Select	Set
Shared	Single	Static
Stop	Sub	Then
To	True	Type
And	As	Boolean
ByRef	Byte	ByVal
Call	Case	Class
Const	Currency	Debug
Dim	Do	Double
Each	Else	ElseIf
Empty	End	EndIf
Enum	Eqv	Event
Exit	False	For
Function	Get	GoTo
If	Imp	Implements
In	Integer	Is
Let	Like	Long
TypeOf	Until	Variant
Wend	While	With
Xor	Eval	Execute
Msgbox	Erase	ExecuteGlobal
Option Exppcit	Randomize	SendKeys

Case Sensitivity

VBScript is a case-insensitive language. This means that language keywords, variables, function names and any other identifiers need NOT be typed with a consistent capitapzation of letters. So identifiers int_counter, INT_Counter and INT_COUNTER have the same meaning within VBScript.

Comments in VBScript

Comments are used to document the program logic and the user information with which other programmers can seamlessly work on the same code in future. It can include information such as developed by, modified by and it can also include incorporated logic. Comments are ignored by the interpreter while execution. Comments in VBScript are denoted by two methods.

1. Any statement that starts with a Single Quote (‘) is treated as comment.

Following is the example −

<script language = "vbscript" type = "text/vbscript">
   <!—
        This Script is invoked after successful login
        Written by : TutorialsPoint
        Return Value : True / False
   //- >
</script>

2. Any statement that starts with the keyword “REM”.