VBScript and Data Types Check
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.
- VarType
- 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.
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