Plaintext Encryption

怎样才能更好的加密一段字符串？MD5、RSA、DES？

好吧，这些都不懂。

参考了一下度娘，所以想法是：

对于加密：

· 从待加密字符串中取出一个字符

· 取字符的低字节和Key1进行异或运算

· 取字符的高字节

· 将运算后的数据合成新的字符

对于解密：

· 从待解密字符串中取出一个字符

· 取字符的低字节和Key1进行异或运算

· 取字符的高字节

· 将运算后的数据合成新的字符

有了方法，可以完成下面的函数：

本加密方法只用于英文，中文也可以加密，但无法解密...

加密 （Encryption）：

Private Function Encrypt(ByVal StrSource As String) As String    '加密
Dim BLowData As Byte
Dim BHigData As Byte
Dim SHigData As Byte
Dim i As Long
Dim k As Integer
Dim StrEncrypt As String
Dim StrChar As String

Dim KeyTemp As String
Dim Key1 As Byte
    For k = 1 To 30
    KeyTemp = KeyTemp & CStr(Int(Rnd * (9) + 1))
    Next
    Key1 = CByte(Mid(KeyTemp, 11, 1) & Mid(KeyTemp, 27, 1))
    For i = 1 To Len(StrSource)
    StrChar = Mid(StrSource, i, 1)  '从待加密字符串中取出一个字符
    BLowData = AscB(MidB(StrChar, 1, 1)) Xor Key1    '取字符的低字节和Key1进行异或运算
    SHigData = AscB(MidB(StrChar, 2, 1))   '取字符的高字节
    StrEncrypt = StrEncrypt & ChrB(BLowData) & ChrB(BHigData)    '将运算后的数据合成新的字符
    Next i
    Encrypt = KeyTemp & StrEncrypt
End Function

解密（Decryption）：

Private Function Decrypt(ByVal StrSource As String) As String     '解密
Dim BLowData As Byte
Dim BHigData As Byte
Dim i As Long
Dim k As Integer
Dim StrDecrypt As String
Dim StrChar As String
Dim KeyTemp As String
Dim Key1 As Byte
KeyTemp = Mid(StrSource, 1, 30)
Key1 = CByte(Mid(KeyTemp, 11, 1) & Mid(KeyTemp, 27, 1))
For i = 31 To Len(StrSource)
StrChar = Mid(StrSource, i, 1)    '从待解密字符串中取出一个字符
BLowData = AscB(MidB(StrChar, 1, 1)) Xor Key1   '取字符的低字节和Key1进行异或运算
BHigData = AscB(MidB(StrChar, 2, 1))      '取字符的高字节
StrDecrypt = StrDecrypt & ChrB(BLowData) & ChrB(BHigData)   '将运算后的数据合成新的字符
Next i
Decrypt = StrDecrypt
End Function

另外，考虑到加密字符的复杂性，建立一个command用来复制到剪贴板：

Private Sub copyl_Click()
Clipboard.Clear
Clipboard.SetText (jiemit.Text)
End Sub

所以：

Option Explicit
'Copyright (c) 2014,烟台大学计算机学院
'All right reserved.
'作者：邵帅
'文件：工程1.vsp
'完成时间：2015年2月26日
'版本号：v1.0.1
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, _
ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
Private Declare Function ReleaseCapture Lib "user32" () As Long
Private Const WM_SYSCOMMAND = &H112
Private Const SC_MOVE = &HF010&
Private Const HTCAPTIO = 2
Private Function Encrypt(ByVal StrSource As String) As String    '加密
Dim BLowData As Byte
Dim BHigData As Byte
Dim SHigData As Byte
Dim i As Long
Dim k As Integer
Dim StrEncrypt As String
Dim StrChar As String

Dim KeyTemp As String
Dim Key1 As Byte
    For k = 1 To 30
    KeyTemp = KeyTemp & CStr(Int(Rnd * (9) + 1))
    Next
    Key1 = CByte(Mid(KeyTemp, 11, 1) & Mid(KeyTemp, 27, 1))
    For i = 1 To Len(StrSource)
    StrChar = Mid(StrSource, i, 1)  '从待加密字符串中取出一个字符
    BLowData = AscB(MidB(StrChar, 1, 1)) Xor Key1    '取字符的低字节和Key1进行异或运算
    SHigData = AscB(MidB(StrChar, 2, 1))   '取字符的高字节
    StrEncrypt = StrEncrypt & ChrB(BLowData) & ChrB(BHigData)    '将运算后的数据合成新的字符
    Next i
    Encrypt = KeyTemp & StrEncrypt
End Function
Private Function Decrypt(ByVal StrSource As String) As String     '解密
Dim BLowData As Byte
Dim BHigData As Byte
Dim i As Long
Dim k As Integer
Dim StrDecrypt As String
Dim StrChar As String
Dim KeyTemp As String
Dim Key1 As Byte
KeyTemp = Mid(StrSource, 1, 30)
Key1 = CByte(Mid(KeyTemp, 11, 1) & Mid(KeyTemp, 27, 1))
For i = 31 To Len(StrSource)
StrChar = Mid(StrSource, i, 1)    '从待解密字符串中取出一个字符
BLowData = AscB(MidB(StrChar, 1, 1)) Xor Key1   '取字符的低字节和Key1进行异或运算
BHigData = AscB(MidB(StrChar, 2, 1))      '取字符的高字节
StrDecrypt = StrDecrypt & ChrB(BLowData) & ChrB(BHigData)   '将运算后的数据合成新的字符
Next i
Decrypt = StrDecrypt
End Function

Private Sub clearl_Click()
jiamit.Text = ""
jiemit.Text = ""
End Sub

Private Sub close_Click()
End
End Sub

Private Sub copyl_Click()
Clipboard.Clear
Clipboard.SetText (jiemit.Text)
End Sub

Private Sub Image1_Click()

End Sub

Private Sub jiamil_Click()
jiemit.Text = Encrypt(jiamit.Text)
End Sub

Private Sub jiemil_Click()
jiemit.Text = Decrypt(jiemit.Text)
End Sub

Private Sub labFormTitle_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
    ReleaseCapture 'WM_SYS向窗体发送一个移动窗体命令
    Call SendMessage(Me.hwnd, WM_SYSCOMMAND, SC_MOVE + HTCAPTIO, 0)
'SC_MOVE+ HTCAPTIO表示单击左键移动窗体
End Sub

Private Sub mini_Click()
If Me.WindowState = 0 Then
  Me.WindowState = 1
End If
End Sub

好吧，顺便写了一个UI，纯英文界面，高大上有木有，还能学习英文，因为写了这段代码，我知道了加密和解密的英文写法。

      、

满满的字符，瞬间猜不透了有木有。 

下载：

Plaintext Encryption

@ Mayuko