VB.NET Language in a Nutshell, Second Edition

Name

VarType Function

Class

Microsoft.VisualBasic.Information

Syntax

VarType(varname)

varname (required; any)

The name of a variable

Return Value

A member of the VariantType enumeration indicating the variable type

Description

Determines the data type of a variable

Rules at a Glance

• The possible values returned by the function include the following members of the VariantType enumeration:

Constant	Value	Description
Array	8192	Array
Boolean	11	Boolean data type
Byte	17	Byte data type
Char	18	Char data type
Date	7	Date data type
Decimal	14	Decimal data type
Double	5	Double data type
Integer	3	Integer data type
Long	20	Long data type
Object	9	Object, uninitialized string, uninitialized array, object of a specific type
Short	2	Short data type
Single	4	Single data type
String	8	String
UserDefinedType	36	A structure

• If varname is a dimensioned array, the VarType function returns VariantType.Array (8192), plus the value of the array’s data type. For example, an array of strings returns 8192 + 8 = 8200. You can test for an array with a code fragment such as the following:

  If VarType(myVar) And VariantType.Array Then

  You can extract the data type of the array with the following code fragment:

  vartype(myVar) and &HFFFFDFFF

• All object variables, whether late-bound or early-bound, return VariantType.Object.

• Data types that are members of the base class library but are not wrapped by VB data types (i.e., UINT16, UINT32 etc.) return VariantType.UserDefinedType ...