1、一、自制函数源代码在网上也找不到解决办法，怎么办？难道我也要放弃VB吗？不！决不！经过苦思冥想，终于鲽判砦吟制作出了用于解决的函数Unsigned()。'有符号转无符号Public Function unSigned(hNum As String) As Double Dim isDbl As Double, fNum As Byte If InStr(hNum, "&H") Then hNum = Replace(hNum, "&H", "") If Len(hNum) <> 8 Then isDbl = "&H" & hNum Else fNum = "&H" & Left(hNum, 1) Do If fNum > 7 Then fNum = fNum - 7 isDbl = isDbl + "&H70000000" Else isDbl = isDbl + ("&H" & fNum & Right(hNum, 7)) Exit Do End If Loop End If unSigned = isDblEnd Function
2、二、原理说明函数Unsigned()接收参数hNum为十六进制数，即然大于等于“&H80000000”的数都是负数，那么我就以“&H70000000”作为一个分界线，只要大于“&H70000000”就减“&H70000000”，然后相加，举例如下：Sub Test_wanao() Dim Eax As Double Eax = unSigned("&H87654321")End Sub函数Unsigned()的工作原理就是：“&H70000000”+"&H17654321"。
3、三、反向转换其实，有些时候，也会需要“无符号转有符号”，所以，我就又制作出了下面这个“无符号转有符号”函数：Public Function Signed(ByValhNum As Double) As Double If hNum < 4294967296# And hNum > 2147483647 Then hNum = hNum - 4294967296# End If Signed = hNumEnd Function这个函数的原理很简单，大于2147483647（即：十六进制“&H7FFFFFFF”）的数全部减4294967296（即：十六进制“&H100000000”，一个1，八个0）。
4、四、测试Sub Test_wanao() Dim Eax As Double, Ebx As Double, Ecx As Double Eax = unSigned("87654321") Ebx = "&H87654321" Ecx = Signed(Eax) StopEnd Sub大家猜一下，Eax、Ebx、Ecx各是多少？首先Ebx为VB默认的有符号型，所以Ebx =-2023406815Eax为无符号型，Eax =2271560481Ecx为有符号型，Ecx=-2023406815
