刚写的加解密函数，但密码不能为汉字
 
   Public Function str_jm(ByVal txtword As String, ByVal txtpass As String) As String
        Dim B1(10), B2(10), B3(10), q1, q2, i, j As Integer
        Dim txtpa As String = ""            '定义待加密字符串

        q1 = Len(txtpass)                        '密码的长度
        ReDim B1(q1)  '重定义数组B1为密码长度
        For j = 1 To q1                             'j=1到q循环
            B1(j) = Asc(Mid(txtpass, j, 1))         '取ASCII码(txtPass,第j(j=1 to q)个开始,取一个字符)
        Next j

        q2 = Len(txtword)                            'q2=textWord的长度
        ReDim B2(q2)  '重定义数组B1为密码长度
        ReDim B3(q2)  '

        For j = 1 To q2                             'j=1到q循环
            B2(j) = Asc(Mid(txtword, j, 1))         '取ASCII码(txtWord,第j(j=1 to q)个开始,取一个字符)
        Next j
        j = 0
        Try
            '开始加密处理
            For i = 1 To q2
                If j < q1 Then
                    j = j + 1
                Else
                    j = 1
                End If
                If B2(i) <> B1(j) Then
                    B3(i) = B2(i) Xor B1(j)
                Else
                    B3(i) = B2(i)
                End If
                txtpa &= Chr(B3(i))
            Next i

        Catch ex As Exception
            MsgBox(ex.Message + Str(B1(j)))

        End Try
        Return txtpa
    End Function

[此贴子已经被作者于2016-9-13 17:52编辑过]

上面是刚用 xor 写的:

str_jm("中国共产主义青年团","3445dfg") 执行一次加密，再执行一次解密 没问题，但
str_jm("中国共产主义青年团","中国")  执行解密出错,为什么汉字密码不能还原呢

本想对所有保存在SQL字段中的字串加密再保存，读回本地后解密再用的