Get the type of a variable in VBScript

问题

How do I get the type of a variable using VBScript?

回答1:

Is VarType what you need?

Returns a value indicating the subtype of a variable.

+--------------+-------+---------------------------------------------+
|   Constant   | Value |                 Description                 |
+--------------+-------+---------------------------------------------+
| vbEmpty      |     0 | Empty (uninitialized)                       |
| vbNull       |     1 | Null (no valid data)                        |
| vbInteger    |     2 | Integer                                     |
| vbLong       |     3 | Long integer                                |
| vbSingle     |     4 | Single-precision floating-point number      |
| vbDouble     |     5 | Double-precision floating-point number      |
| vbCurrency   |     6 | Currency                                    |
| vbDate       |     7 | Date                                        |
| vbString     |     8 | String                                      |
| vbObject     |     9 | Automation object                           |
| vbError      |    10 | Error                                       |
| vbBoolean    |    11 | Boolean                                     |
| vbVariant    |    12 | Variant (used only with arrays of Variants) |
| vbDataObject |    13 | A data-access object                        |
| vbDecimal    |    14 | Decimal Value                               |
| vbByte       |    17 | Byte                                        |
| vbLongLong   |    20 | LongLong integer (64 bit)                   |
| vbArray      |  8192 | Array                                       |
+--------------+-------+---------------------------------------------+

The VarType function never returns the value for Array by itself. It is always added to some other value to indicate an array of a particular type. The value for Variant is only returned when it has been added to the value for Array to indicate that the argument to the VarType function is an array. For example, the value returned for an array of integers is calculated as 2 + 8192, or 8194. If an object has a default property, VarType (object) returns the type of its default property.

回答2:

If you want to get the type name of an object assigned to a variable with Set, you can use TypeName instead.

Class SomeClass
    '' empty class
End Class

Dim x
Set x = New SomeClass
WScript.Echo TypeName(x)  '' displays "SomeClass"

回答3:

Tmdean's answer also works to get the Type Name (not an integer) of (almost) all other types of variables (per http://msdn.microsoft.com/en-us/library/ie/y58s1cs6%28v=vs.84%29.aspx)

dim i,s,a
i = 1
s = "Hello world"
a = split("Hello World"," ")

WScript.Echo TypeName(i) 'Displays "Integer"
WScript.Echo TypeName(s) 'Displays "String"
WScript.Echo TypeName(a) 'Displays "Variant()"

回答4:

Dim a, b, c, d, e, f
a = 10
b = "text"
c = Split("John Doe,Jane Smith,Dick Tracy", ",")
d = 1.2
e = Null
f = True
MsgBox "'a' is " & fVarType(a) & vbNewLine & _
       "'b' is " & fVarType(b) & vbNewLine & _
       "'c' is " & fVarType(c) & vbNewLine & _
       "'d' is " & fVarType(d) & vbNewLine & _
       "'e' is " & fVarType(e) & vbNewLine & _
       "'f' is " & fVarType(f) & vbNewLine & _
       "'g' is " & fVarType(c(0))

Function fVarType(x)
    Const ArrayCode = 8192
    Dim y
    y = VarType(x)
    If y < ArrayCode Then
        fVarType = fGetType(VarType(x))
    Else
        fVarType = "vbArray with " & fGetType(VarType(x)- ArrayCode) & " elements"
    End If  
End Function

Function fGetType(vType)
    Select Case vType   
        Case 0 fGetType = "vbEmpty"
        Case 1 fGetType = "vbNull"
        Case 2 fGetType = "vbInteger"
        Case 3 fGetType = "vbLong"
        Case 4 fGetType = "vbSingle"
        Case 5 fGetType = "vbDouble"
        Case 6 fGetType = "vbCurrency"
        Case 7 fGetType = "vbDate"
        Case 8 fGetType = "vbString"
        Case 9 fGetType = "vbObject"
        Case 10 fGetType = "vbError"
        Case 11 fGetType = "vbBoolean"
        Case 12 fGetType = "vbVariant"
        Case 13 fGetType = "vbDataObject"
        Case 14 fGetType = "vbDecimal"
        Case 17 fGetType = "vbByte"
        Case Else fGetType = "undetected"
    End Select
End Function

回答5:

vartype is appropriate ...

Dim x
x=123
msgbox VarType(x)

回答6:

Dim TypeDictionary

Set TypeDictionary = CreateObject("Scripting.Dictionary")
TypeDictionary.Add 0, "vbEmpty"
TypeDictionary.Add 1, "vbNull"
TypeDictionary.Add 2, "vbInteger"
TypeDictionary.Add 3, "vbLong"
TypeDictionary.Add 4, "vbSingle"
TypeDictionary.Add 5, "vbDouble"
TypeDictionary.Add 6, "vbCurrency"
TypeDictionary.Add 7, "vbDate"
TypeDictionary.Add 8, "vbString"
TypeDictionary.Add 9, "vbObject"
TypeDictionary.Add 10, "vbError"
TypeDictionary.Add 11, "vbBoolean"
TypeDictionary.Add 12, "vbVariant"
TypeDictionary.Add 13, "vbDataObject"
TypeDictionary.Add 17, "vbByte"

Public Function GetType(argument)
    GetType = TypeDictionary.Item(VarType(argument))
End Function

This version invests more effort setting up the dictionary, but then looks up any type in one check(fingers crossed) rather than checking every single type every single time.

equivalent JScript code(hypothetical, since JScript has typeof, and lacks many vb types):

var TypeDictionary = {
    0: 'vbEmpty',
    1: 'vbNull',
    2: 'vbInteger',
    3: 'vbLong',
    4: 'vbSingle',
    5: 'vbDouble',
    6: 'vbCurrency',
    7: 'vbDate',
    8: 'vbString',
    9: 'vbObject',
    10: 'vbError',
    11: 'vbBoolean',
    12: 'vbVariant',
    13: 'vbDataObject',
    17: 'vbByte'
};

var GetType = function() {
    return TypeDictionary[arguments[0]];
};

来源：https://stackoverflow.com/questions/3281355/get-the-type-of-a-variable-in-vbscript

标签

asp-classic

vbscript