是否有一个函数内建到VBScript (wscript
或cscript
),将采取一个数字,并将其转换为基数2?
例如,Base2(45)
将输出"101101"
我不知道有什么内置的,但是创建一个可以处理二进制和其他基数的通用例程很容易。例如,如果您定义从0
到Z
的符号,则可以处理以36为基数的所有符号。
Function ToBase(ByVal n, b)
' Handle everything from binary to base 36...
If b < 2 Or b > 36 Then Exit Function
Const SYMBOLS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
Do
ToBase = Mid(SYMBOLS, n Mod b + 1, 1) & ToBase
n = Int(n / b)
Loop While n > 0
End Function
对于您的示例,只需传递2
作为基础:
WScript.Echo ToBase(45, 2)
输出:101101
将负数编码为二进制,如calc
在编程模式,即仅整数模式(但VBScript
仅将精度降低到32位):
option explicit
On Error GoTo 0
Dim xx
xx = 45
Wscript.Echo +xx, vbTab, Base2( xx, False), Base2( xx, True)
Wscript.Echo -xx, vbTab, Base2(-xx, False), Base2(-xx, True)
Function Base2( iNum, bLong)
Dim ii, octets, sNum, iLen
octets = Array ( "000","001", "010", "011", "100", "101", "110", "111")
If bLong Or Len( CStr( Hex( -Abs(iNum)))) > 4 Then
sNum = CStr( Oct(CLng(iNum))) 'force Long : DWORD (32 bits/4 bytes)
iLen = 32
Else
sNum = CStr( Oct(CInt(iNum))) 'keep Integer: WORD (16 bits/2 bytes)
iLen = 16
End If
Base2 = ""
For ii = 1 To Len( sNum)
Base2 = Base2 & octets( Mid( sNum, ii, 1))
Next
Do While Len( Base2) > 1 And Left( Base2, 1) = "0"
Base2 = Mid( Base2, 2) 'truncate left zeroes
Loop
'expand left zeroes for a positive value?
'Base2 = Right( String( iLen, "0") & Base2, iLen)
End Function
:
==>cscript //NOLOGO D:VB_scriptsSO32416311.vbs
45 101101 101101
-45 1111111111010011 11111111111111111111111111010011
==>
输出 Base2 = Right( String( iLen, "0") & Base2, iLen)
未注释:
==>cscript //NOLOGO D:VB_scriptsSO32416311.vbs
45 0000000000101101 00000000000000000000000000101101
-45 1111111111010011 11111111111111111111111111010011
==>
从c库代码中偷来的更通用(也更安全)的方法:
Option Explicit
Function ntoa( nNum, iBase )
ntoa = "0"
If nNum Then
ntoa = Mid( "-", Sgn( nNum ) + 2 ) + ntoaPos( Abs( nNum ), iBase )
End If
End Function
Function ntoaPos( nNum, iBase )
If nNum >= 1 Then
Dim nD : nD = Fix( nNum / iBase )
Dim nM : nM = nNum - nD * iBase
ntoaPos = ntoaPos( nD, iBase ) _
& Mid( "0123456789ABCDEFGHIJKLMNOPQRSTUV", 1 + nM, 1 )
End If
End Function
Function aton( ByVal sNum, iBase )
sNum = Trim( sNum )
Dim nLen : nLen = Len( sNum )
Dim bNeg, nPos
Select Case Left( sNum, 1 )
Case "+"
bNeg = False
nPos = 2
Case "-"
bNeg = True
nPos = 2
Case Else
bNeg = False
nPos = 1
End Select
aton = "0"
For nPos = nPos To nLen
Dim nAdd : nAdd = Instr( "0123456789ABCDEFGHIJKLMNOPQRSTUV", Mid( sNum, nPos, 1 ) )
If 0 = nAdd Then
' Error
End If
aton = aton * iBase + nAdd - 1
Next
If bNeg Then
aton = - aton
End If
End Function
' use ByVal or don't change the parameter!
Function ToBase(ByVal n, b)
' Handle everything from binary to base 36...
If b < 2 Or b > 36 Then Exit Function
Const SYMBOLS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
Do
ToBase = Mid(SYMBOLS, n Mod b + 1, 1) & ToBase
n = Int(n / b)
Loop While n > 0
End Function
Dim xTests
Dim oWAU : Set oWAU = WScript.Arguments.Unnamed
If 0 = oWAU.Count Then
Set xTests = CreateObject("System.Collections.ArrayList")
xTests.Add 45
xTests.Add 2
Else
Set xTests = WScript.Arguments.Unnamed
End If
Dim i, n, b, s, o, r
For i = 1 To xTests.Count Step 2
n = Eval(xTests(i - 1))
b = xTests(i)
s = ntoa(n, b)
On Error Resume Next
o = ToBase(n, b)
If Err.Number Then
o = Err.Description
End If
On Error GoTo 0
r = aton(s, b)
WScript.Echo n, b, "==>", s, "<==", r, "?", CStr(n = r), o
Next
输出:cscript 32416311-2.vbs 45 2 12345 16 "2^33" 16 -45 2 "2^50" 8 "2^50*-1" 32 "&HFF" 10
45 2 ==> 101101 <== 45 ? True 101101
12345 16 ==> 3039 <== 12345 ? True 3039
8589934592 16 ==> 200000000 <== 8589934592 ? True Overflow
-45 2 ==> -101101 <== -45 ? True Invalid procedure call or argument
1,12589990684262E+15 8 ==> 40000000000000000 <== 1,12589990684262E+15 ? True Overflow
-1,12589990684262E+15 32 ==> -10000000000 <== -1,12589990684262E+15 ? True Overflow
255 10 ==> 255 <== 255 ? True 255