当把C代码翻译到VB时，你经常会遇到高字和低字的操作，通常是把两个整型值合成一个长整型。当在C代码中使用了无符号整型，这最高一位是可以被设置的，因此简单的直接转换高字将会遇到困难。由于VB不支持无符号算术符，我们只好剥去这最高一位，在稍后再把它加回来，以避免溢出和错误的结果。（WXJ_Lake 译）
开始一个新工程，增添一个标准模块。把以下代码写入模块：
Start a new project then add a module. Add the following code to the module:
Public Property Get LoWord(ByRef lThis As Long) As Long
LoWord = (lThis And &HFFFF&)
End Property
Public Property Let LoWord(ByRef lThis As Long, ByVal lLoWord As Long)
lThis = lThis And Not &HFFFF& Or lLoWord
End Property
Public Property Get HiWord(ByRef lThis As Long) As Long
If (lThis And &H80000000) = &H80000000 Then
HiWord = ((lThis And &H7FFF0000) / &H10000) Or &H8000&
Else
HiWord = (lThis And &HFFFF0000) / &H10000
End If
End Property
Public Property Let HiWord(ByRef lThis As Long, ByVal lHiWord As Long)
If (lHiWord And &H8000&) = &H8000& Then
lThis = lThis And Not &HFFFF0000 Or ((lHiWord And &H7FFF&) * &H10000) Or &H80000000
Else
lThis = lThis And Not &HFFFF0000 Or (lHiWord * &H10000)
End If
End Property
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