vb中如何對字符串進行加密和解密（有漢字的）

Public Function StringEnDeCodecn(strSource As String, MA) As String

'該函數只對中西文起到加密作用

'參數為：源文件，密碼

On Error GoTo ErrEnDeCode

Dim X As Single

Dim CHARNUM As Long, RANDOMINTEGER As Integer

Dim SINGLECHAR As String * 1

Dim strTmp As String

If MA < 0 Then

MA = MA * (-1)

End If

X = Rnd(-MA)

For i = 1 To Len(strSource) Step 1 '取單字節內容

SINGLECHAR = Mid(strSource, i, 1)

CHARNUM = Asc(SINGLECHAR)

g: RANDOMINTEGER = Int(127 * Rnd)

If RANDOMINTEGER < 30 Or RANDOMINTEGER > 100 Then GoTo g

CHARNUM = CHARNUM Xor RANDOMINTEGER

strTmp = strTmp & Chr(CHARNUM)

Next i

StringEnDeCodecn = strTmp

Exit Function

ErrEnDeCode:

StringEnDeCodecn = ""

MsgBox Err.Number & "\" & Err.Description

End Function

使用方法：

tmp=stringEnDecn("中華人民***和國",75)

如果要解密的話，只須鍵入以下語句：

tmp1=stringendecn(tmp,75)