10进制转换16进制(转换结果最大支持24个F)

10进制转换16进制(转换结果最大支持24个F)

Private Sub Form_Load()
    Dim a As String, b As String
   
    a = "79228162514264337593543950335" '这是VB能处理的最大整数Decimal类型24个F,
                                                                        '计算器转换此数到16进制时已经溢出得16个F
    b = DecToHex(a)
    Debug.Print b
 
    a = "18446744073709551615" '这个数属Decimal类型转换后16个F
    b = DecToHex(a)
    Debug.Print b
 
    a = "4294967295" '这是C语言无符号长整的最大数8个F
    b = DecToHex(a)
    Debug.Print b
   
    a = "65535" '这是C语言无符号整形最大数4个F
    b = DecToHex(a)
    Debug.Print b
   
    a = "1234567890" '随便给个不出错的数,可以对照计算机器的值
    b = DecToHex(a)
    Debug.Print b
   
    a = "1111111111a1111111111"   '这是一个出错的例子
    b = DecToHex(a)
    Debug.Print b

End Sub

Private Function DecToHex(ByVal c As String) As String
'10进制转16进制函数
'24个F以下(含24个F)的数不会出错
  On Error GoTo imsg
  Dim a, b, i As Integer, m As Integer
  Dim iH() As String, iHex As String
    If c = "0" Then
       DecToHex = 0
       Exit Function
    End If
   
    a = CDec(c)
    b = CDec(b)
   
    While a > 0
        ReDim Preserve iH(i)
        b = Int(a / 16)
        iH(i) = a - b * 16
        a = b
        i = i + 1
    Wend
    For m = i - 1 To 0 Step -1
        iHex = iHex & Hex(iH(m))
    Next
    DecToHex = iHex
    Exit Function
imsg:
    Debug.Print "原数据错误!";
    DecToHex = ""
End Function