QTP - VBScript and Data Types

How do we find Data Type of a Variable in VBScript?

The data type of a variable can be indentified in two VBScript built-in functions.

1. VarType
2. TypeName

VarType :

The VarType function returns a value indicating the subtype of a variable.

Syntax : VarType(varname)

varname :The varname argument can be any variable.

TypeName :

The TypeName function returns a string containing the name of the data type of a variable.

Syntax : TypeName(varname)

varname : Required. The name of a variable.

VarType returns a numeric value indicating the sub datatype of a variable.

TypeName directly returns the name of the Sub Datatype of a variable.

VarType

The below table contains return values that indicate respective subtypes.

Return Value	Sub Datatype	Description
0	vbEmpty	Empty (uninitialized)
1	vbNull	Null (no valid data)
2	vbInteger	Integer
3	vbLong	Long integer
4	vbSingle	Single-precision floating-point number
5	vbDouble	Double-precision floating-point number
6	vbCurrency	Currency
7	vbDate	Date
8	vbString	String
9	vbObject	Automation object
10	vbError	Error
11	vbBoolean	Boolean
12	vbVariant	Variant (used only with arrays of Variants)
13	vbDataObject	A data-access object
17	vbByte	Byte
8192	vbArray	Array

Examples:

Dim MyCheck

MyCheck = VarType(300)          ' Returns 2.

MyCheck = VarType(#10/19/62#)   ' Returns 7.

MyCheck = VarType("VBScript")   ' Returns 8.

TypeName directly returns the name of the Sub Datatype of a variable.

TypeName

Sub Datatype	Description
Byte	Byte value
Integer	Integer value
Long	Long integer value
Single	Single-precision floating-point value
Double	Double-precision floating-point value
Currency	Currency value
Decimal	Decimal value
Date	Date or time value
String	Character string value
Boolean	Boolean value; True or False
Empty	Unitialized
Null	No valid data
<object type>	Actual type name of an object
Object	Generic object
Unknown	Unknown object type
Nothing	Object variable that doesn't yet refer to an object instance
Error	Error

Examples:

Dim ArrayVar(4), MyType

NullVar = Null   ' Assign Null value.

MyType = TypeName("VBScript")   ' Returns "String".

MyType = TypeName(4)            ' Returns "Integer".

MyType = TypeName(37.50)        ' Returns "Double".

MyType = TypeName(NullVar)      ' Returns "Null".

MyType = TypeName(ArrayVar)     ' Returns "Variant()".

There are some more VBScript Built-in functions to find whether a variable datatype is specific datatype or not.

IsArray – Returns a Boolean value indicating whether a variable is an array or not.

IsDate – Returns a Boolean value indicating whether an expression can be converted to a date.

IsEmpty – Returns a Boolean value indicating whether a variable has been initialized.

IsNull - Returns a Boolean value that indicates whether an expression contains no valid data (Null).

IsNumeric - Returns a Boolean value indicating whether an expression can be evaluated as a number.

IsObject - Returns a Boolean value indicating whether an expression references a valid Automation object.

Posted in: QTP - VBScript and Data Types