好象有个StrReverse函数是直接反转字符串的吧..
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我平时用的是VB6.但是.NET中应该也是可以用MID的
你注意看FOR 是从len-1到0的..而mid中是不允许出现0的..
你看看MID运行不了时,是不是返回I是0的时间
改成:
For i = Len(sstr) To 1 Step -1
试试了?
字符编码转换吗?
1.字符与gb2312(gbk的子集)：
Public Function GBKEncode(ByVal sInput As String) As String
Dim ret_GBKEncode As String = ""
Dim i As Integer
Dim startIndex As Integer = 0
Dim endIndex As Integer
Dim x() As Byte = System.Text.Encoding.Default.GetBytes(sInput) '字符以及字符串在vb2008中都是以unicode编码存储的
endIndex = x.Length - 1
For i = startIndex To endIndex
ret_GBKEncode = "%" Hex(x(i))
Next
Return ret_GBKEncode
End Function
'GBK解码
Public Function GBKDecode(ByVal sInput As String) As String
sInput = sInput.Replace("%", "")
Dim ret_GBKDecode As String = ""
Dim sLen As Integer = sInput.Length
Dim n As Integer = sLen \ 2
Dim sBytes(0 To n - 1) As Byte
'转化为字节码
For i As Integer = 1 To n
sBytes(i - 1) = CByte("H" sInput.Substring(2 * i - 2, 2))
Next
'将字节码转化为字符串
ret_GBKDecode = System.Text.Encoding.Default.GetString(sBytes)
Return ret_GBKDecode
End Function
2.Unicode字符串为UTF-8
Imports System.Text
Public Function StringAsUtf8Bytes(ByVal strData As String) As Byte()
Dim bytes() As Byte
bytes = Encoding.UTF8.GetBytes(strData)
Return bytes
End Function
'这里可以类推出好几种。
文字编辑结束后，选择“移动”工具（工具箱第一个工具，快捷键V），然后按Ctrl+T快捷键进行“自由变换”，会在文字上出现控制框，把鼠标移到控制框外边指针就会变成旋转的样式，按住鼠标左键拖动就可以进行任意角度旋转了。
明白你的意思了,只要是字母都会转换成数字,帮你写好了("usernane"和 "pasward" 我这里写成 "username" 和" password"）
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim username, password As String
Dim temp As Long
Dim r As String = ""
Dim v As String = TextBox1.Text
For Each c In v.ToString
If IsNumeric(c) Then
r = c
Else
r = ((Asc(c) - 65).ToString("00"))
End If
Next
username = r
temp = username * 3 - 500
password = CStr(temp)
TextBox2.Text = password
End Sub