Question

急求VB程序改错题高手，每个FOUND下一行有错误，请改正！十万火急！明天考试了！

'题目：下面的程序段的功能是：读入八进制数，将其转
' 换成把十进制数

'------------------------------------------------
Option Explicit
Private Sub Form_Click()
Dim oct_num As String
Dim length As Integer, s As Integer, n As Integer, i As Integer, d As String, j As String
oct_num = InputBox("请输入一八进制数")
'**********FOUND**********
length = length(oct_num)
s = 0
n = 0
'**********FOUND**********
For i = length To 1
d = Mid(oct_num, i, 1)
s = s + d * 8 ^ n
n = n + 1
'**********FOUND**********
Loop
Print "十进制数是:"; s
End Sub

Option Explicit

Answer 1

Option Explicit
Private Sub Form_Click()
Dim oct_num As String
Dim length As Integer, s As Integer, n As Integer, i As Integer, d As String, j As String
oct_num = InputBox("请输入一八进制数")
'**********FOUND**********
length = len(oct_num)
s = 0
n = 0
'**********FOUND**********
For i = length To 1 Step -1
d = Mid(oct_num, i, 1)
s = s + d * 8 ^ n
n = n + 1
'**********FOUND**********
Next
Print "十进制数是:"; s
End Sub

追问

最后一个不应该是"Next i”么？

追答

一样，i可以不写

Answer 2

Dim a, b As Integer
oct_num = InputBox("请输入一八进制数")
For i = 1 To oct_num.Length
b = Mid(oct_num, i, 1)
a = (a + b) * 8
Next
MsgBox(a / 8)

Answer 3

①length = len(oct_num)

②For i = length To 1 step -1
d = Mid(oct_num, i, 1)
s = s + d * 8 ^ n
n = n + 1
'**********FOUND**********
Next

Answer 4

1）length = len(oct_num)
2) For i = length To 1 step -1
3) next i