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Data Type Conversions

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Each programming language defines certain types and containers for data. Most of these data types, especially the primitives, map easily to other programming languages. Some data types, however, have no equivalent in another language and cannot be converted.

For specific information about data types not recognized by your programming language, see the following topics:

The following table lists conversions between programming languages for common data types.

C++ Visual Basic Java Contains
signed char
 Not supported
 byte
 1-byte signed integer
(VT_I1, [T])
unsigned char
 Byte
 Not supported
 1-byte unsigned integer
(VT_UI1, [V][T][P][S])
unsigned char
 Character
 char
 2-byte Unicode character
(VT_UI2, [T][P])
short
 Integer
 short
 2-byte signed integer
(VT_I2, [V][T][P][S])
unsigned short
 Not supported
 Not supported
 2-byte unsigned integer
(VT_UI2, [T][P])
int
 Long
 int
 4-byte signed integer
(VT_I4, [V][T][P][S])
unsigned int
 Not supported
 Not supported
 4-byte unsigned integer
(VT_UI4, [T][P])
__int64
 Not supported
 long
 8-byte signed integer
(VT_I8, [T][P])
unsigned __int64
 Not supported
 Not supported
 8-byte unsigned integer
(VT_UI8, [T][P])
float
 Single
 float
 4-byte floating-point number
(VT_R4, [V][T][P][S])
double
 Double
 double
 8-byte floating-point number
(VT_R8, [V][T][P][S])
BSTR
 String
 java.lang.String
 Automation string
(VT_BSTR, [V][T][P][S])
BOOL
 Boolean
 boolean
 Boolean
(VT_BOOL, [V][T][P][S])
VARIANT
 Variant
 com.ms.com.Variant
 VARIANT FAR*
(VT_VARIANT, [V][T][P][S])
IUnknown
 object
 com.ms.com.IUnknown
 IDispatch interface pointer
(VT_DISPATCH, [V][T][P][S])
DATE
 Date
 com.ms.com.Variant
 Date
(VT_DATE, [V][T][P][S])
CURRENCY
 Currency
 com.ms.com.Variant
 Currency
(VT_CY, [V][T][P][S] or VT_DECIMAL, [V][T][S])

For information about VARTYPE values and how to use them, see the topic IDispatch Data Types and Structures.

The data type conversions between scripting languages are simpler than those for programming languages. JScript and JavaScript both support the same data types, and VBScript supports only a single data type, Variant. Thus, all JScript and JavaScript data types become Variant types when converted to VBScript. When you convert VBScript to JScript or JavaScript, the Variant types become numbers, strings, Boolean values, and so on.