v6j06-14字符加密.frm

这是一个vb字符加密的小程序的设计

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "字符加密"
   ClientHeight    =   3270
   ClientLeft      =   1110
   ClientTop       =   1515
   ClientWidth     =   5970
   LinkTopic       =   "Form1"
   PaletteMode     =   1  'UseZOrder
   ScaleHeight     =   3270
   ScaleWidth      =   5970
   Begin VB.CommandButton cmdCls 
      Caption         =   "清屏"
      BeginProperty Font 
         Name            =   "MS Sans Serif"
         Size            =   12
         Charset         =   0
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   495
      Left            =   240
      TabIndex        =   6
      Top             =   2160
      Width           =   975
   End
   Begin VB.TextBox txtRecode 
      BeginProperty Font 
         Name            =   "MS Sans Serif"
         Size            =   12
         Charset         =   0
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   495
      Left            =   1560
      TabIndex        =   5
      Text            =   " "
      Top             =   1440
      Width           =   3375
   End
   Begin VB.CommandButton cmdRecode 
      Caption         =   "解密"
      BeginProperty Font 
         Name            =   "MS Sans Serif"
         Size            =   12
         Charset         =   0
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   495
      Left            =   240
      TabIndex        =   4
      Top             =   1440
      Width           =   975
   End
   Begin VB.TextBox txtCode 
      BeginProperty Font 
         Name            =   "MS Sans Serif"
         Size            =   12
         Charset         =   0
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   495
      Left            =   1560
      TabIndex        =   3
      Text            =   " "
      Top             =   720
      Width           =   3375
   End
   Begin VB.CommandButton cmdCode 
      Caption         =   "加密"
      BeginProperty Font 
         Name            =   "MS Sans Serif"
         Size            =   12
         Charset         =   0
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   495
      Left            =   240
      TabIndex        =   2
      Top             =   720
      Width           =   975
   End
   Begin VB.TextBox txtInput 
      BeginProperty Font 
         Name            =   "MS Sans Serif"
         Size            =   12
         Charset         =   0
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   420
      Left            =   1560
      TabIndex        =   1
      Text            =   " "
      Top             =   120
      Width           =   3375
   End
   Begin VB.Label Labinput 
      Caption         =   "输入字符串"
      BeginProperty Font 
         Name            =   "MS Sans Serif"
         Size            =   12
         Charset         =   0
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   375
      Left            =   240
      TabIndex        =   0
      Top             =   120
      Width           =   1815
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Dim strInput$, Code$, Record$, c As String * 1
Dim i%, length%, iAsc%

Private Sub cmdcls_Click()          '清屏
  txtCode.Text = ""
  txtRecode.Text = ""
  txtInput.Text = ""
End Sub

Private Sub cmdcode_Click()         '加密
  Dim strInput$, Code$, Record$, c As String * 1
  Dim i%, length%, iAsc%
  strInput = txtInput.Text
  length = Len(RTrim(strInput))     '去掉字符串右边的空格,求真正的长度
  Code = ""
  For i = 1 To length
    c = Mid$(strInput, i, 1)        '取第i个字符
    Select Case c
      Case "A" To "Z"               '大写字母加序数5加密
        iAsc = Asc(c) + 5
        If iAsc > Asc("Z") Then iAsc = iAsc - 26   '加密后字母超过Z
        Code = Code + Chr$(iAsc)
      Case "a" To "z"
        iAsc = Asc(c) + 5           '小写字母加序数5加密
        If iAsc > Asc("z") Then iAsc = iAsc - 26
        Code = Code + Chr$(iAsc)
      Case Else                      '当第i个字符为其它字符时不加密,与加密字符串的前i-1个字符连接
        Code = Code + c
    End Select
  Next i
  txtCode.Text = Code                '显示加密后的字符串
End Sub

Private Sub cmdrecode_Click()       '解密与加密正好逆处理
  Code = txtCode.Text
  i = 1
  recode = ""
  length = Len(RTrim(Code))         '若还未加密,不能解密,出错
  If length = 0 Then J = MsgBox("先加密再解密", 48, "解密出错")
  Do While (i <= length)
    c = Mid$(Code, i, 1)
    If (c >= "A" And c <= "Z") Then
      iAsc = Asc(c) - 5
      If iAsc < Asc("A") Then iAsc = iAsc + 26
        recode = Left$(recode, i - 1) + Chr$(iAsc)
    ElseIf (c >= "a" And c <= "z") Then
      iAsc = Asc(c) - 5
      If iAsc < Asc("a") Then iAsc = iAsc + 26
      recode = Left$(recode, i - 1) + Chr$(iAsc)
    Else
      recode = Left$(recode, i - 1) + c
    End If
    i = i + 1
    Loop
  txtRecode.Text = recode
End Sub