这个问题的意思是在原字符里面输进字符串，然后点转换键后，在密码框里出现转换为ASCII后的数字。
在密码框里输进ASCII码后按解密能在原字符框里面转换成字符，就这个意思。

Private Sub Cmd1_Click()
Dim change As Variant
change = Txt1.Text
aa = Len(change)
For i = 1 To aa
bb = bb + Trim(Str(Asc(Mid(change, i, 1))))
Next
Txt2.Text = bb
End Sub

Private Sub Cmd2_Click()
Dim number, bb As Variant
change = Txt2.Text
aa = Len(number)
For i = 1 To aa Step 2
bb = bb + Chr(Mid(number, i, 1))
Next
Txt3.Text = bb
End Sub

现在只有转换为ASCII码可用，ASCII转成字符弄了好久还是不会，
大家帮我一把吧~~HOHO

[此贴子已经被作者于2006-3-24 11:22:08编辑过]

Private Sub Cmd1_Click()
Dim change As Variant
change = Txt1.Text
aa = Len(change)
For i = 1 To aa
bb = bb + Trim(Str(Asc(Mid(change, i, 1))))
Next
Txt2.Text = bb
End Sub

Private Sub Cmd2_Click()
Dim number, bb As Variant
change = Txt2.Text
aa = Len(number)
For i = 1 To aa Step 2
bb = bb + Chr(Mid(number, i, 1))
Next
Txt3.Text = bb
End Sub

错误不少啊！首先你的number是？什么？change是不是写错了？应该是number

你的chr转换虽然是step ！但是后面你写的（bb = bb + Chr(Mid(number, i,1))
）是1不是2！！
而且如果是汉字的话就差的更离谱了！

For循环里的i的问题吧，你试试定义i，然后先给i初始化，在进入For循环