地狱?天堂?

Function URLDecode(enStr)
    Dim deStr
    Dim c, i, v
    deStr = ""
    For i = 1 To Len(enStr)
        c = Mid(enStr, i, 1)
        If c = "%" Then
            v = Eval("&h" + Mid(enStr, i + 1, 2))
            If v < 128 Then
                deStr = deStr & Chr(v)
                i = i + 2
            Else
                If isvalidhex(Mid(enStr, i, 3)) Then
                    If isvalidhex(Mid(enStr, i + 3, 3)) Then
                        v = Eval("&h" + Mid(enStr, i + 1, 2) + Mid(enStr, i + 4, 2))
                        deStr = deStr & Chr(v)
                        i = i + 5
                    Else
                        v = Eval("&h" + Mid(enStr, i + 1, 2) + CStr(Hex(Asc(Mid(enStr, i + 3, 1)))))
                        deStr = deStr & Chr(v)
                        i = i + 3
                    End If
                Else
                    deStr = deStr & c
                End If
            End If
        Else
            If c = "+" Then
                deStr = deStr & " "
            Else
                deStr = deStr & c
            End If
        End If
    Next
    URLDecode = deStr
End Function

Function isvalidhex(str)
    Dim c
    isvalidhex = True
    str = UCase(str)
    If Len(str) <> 3 Then
        isvalidhex = False
        Exit Function
    End If
    If Left(str, 1) <> "%" Then
        isvalidhex = False
        Exit Function
    End If
    c = Mid(str, 2, 1)
    If Not (((c >= "0") And (c <= "9")) Or ((c >= "A") And (c <= "Z"))) Then
        isvalidhex = False
        Exit Function
    End If
    c = Mid(str, 3, 1)
    If Not (((c >= "0") And (c <= "9")) Or ((c >= "A") And (c <= "Z"))) Then
        isvalidhex = False
        Exit Function
    End If
End Function