form1.frm

这个是一个用VB开发的可以实现对输入字符窜的加密/解密

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "密码解密"
   ClientHeight    =   3765
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   5985
   LinkTopic       =   "Form1"
   ScaleHeight     =   3765
   ScaleWidth      =   5985
   StartUpPosition =   3  '窗口缺省
   Begin VB.CommandButton cmdcls 
      Caption         =   "请屏"
      Height          =   375
      Left            =   480
      TabIndex        =   6
      Top             =   3000
      Width           =   975
   End
   Begin VB.TextBox txtrecode 
      Height          =   375
      Left            =   1920
      TabIndex        =   5
      Top             =   2160
      Width           =   2655
   End
   Begin VB.TextBox txtcode 
      Height          =   375
      Left            =   1920
      TabIndex        =   4
      Top             =   1320
      Width           =   2655
   End
   Begin VB.CommandButton cmdrecode 
      Caption         =   "解密"
      Height          =   375
      Left            =   480
      TabIndex        =   3
      Top             =   2160
      Width           =   975
   End
   Begin VB.CommandButton cmdcode 
      Caption         =   "加密"
      Height          =   375
      Left            =   480
      TabIndex        =   2
      Top             =   1320
      Width           =   975
   End
   Begin VB.TextBox txtinput 
      Height          =   375
      Left            =   1920
      TabIndex        =   1
      Top             =   480
      Width           =   2655
   End
   Begin VB.Label Label1 
      AutoSize        =   -1  'True
      Caption         =   "输入字符串"
      Height          =   180
      Left            =   600
      TabIndex        =   0
      Top             =   600
      Width           =   900
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Dim strinput As String * 70, code As String * 70
Dim recode As String, strtemp As String * 1
Dim i As Integer, length As Integer
Dim iasc As Integer

Private Sub cmdcls_Click()
    txtcode.Text = ""
    txtrecode.Text = ""
    txtinput.Text = ""
End Sub

Private Sub cmdcode_Click()
    strinput = txtinput.Text
    i = 1
    code = ""
    length = Len(RTrim(strinput))
    Do While (i <= length)
        strtemp = Mid$(strinput, i, 1)
        If (strtemp >= "A" And strtemp <= "Z") Then
            iasc = Asc(strtemp) + 5
            If iasc > Asc("Z") Then iasc = iasc - 26
            code = Chr$(iasc)
            txtcode.Text = RTrim(txtcode.Text) & RTrim(code)
        ElseIf (strtemp >= "a" And strtemp <= "z") Then
            iasc = Asc(strtemp) + 5
            If iasc > Asc("z") Then iasc = iasc - 26
            code = Chr$(iasc)
            txtcode.Text = RTrim(txtcode.Text) & RTrim(code)
        ElseIf (strtemp >= "0" And strtemp <= "9") Then
            iasc = strtemp + 5
            If iasc > "9" Then iasc = iasc - 10
            txtcode.Text = RTrim(txtcode.Text) & RTrim(iasc)
        Else
            code = strtemp
            txtcode.Text = RTrim(txtcode.Text) & RTrim(code)
        End If
        i = i + 1
        Loop
End Sub

Private Sub cmdrecode_Click()
    strinput = txtcode.Text
    i = 1
    code = ""
    length = Len(RTrim(strinput))
    Do While (i <= length)
        strtemp = Mid$(strinput, i, 1)
        If (strtemp >= "A" And strtemp <= "Z") Then
            iasc = Asc(strtemp) - 5
            If iasc < Asc("A") Then iasc = iasc + 26
            code = Chr$(iasc)
            txtrecode.Text = RTrim(txtrecode.Text) & RTrim(code)
        ElseIf (strtemp >= "a" And strtemp <= "z") Then
            iasc = Asc(strtemp) - 5
            If iasc < Asc("a") Then iasc = iasc + 26
            code = Chr$(iasc)
            txtrecode.Text = RTrim(txtrecode.Text) & RTrim(code)
        ElseIf (strtemp >= "0" And strtemp <= "9") Then
            iasc = strtemp - 5
            If iasc < "0" Then iasc = iasc + 10
            txtrecode.Text = RTrim(txtrecode.Text) & RTrim(iasc)
        Else
            code = strtemp
            txtrecode.Text = RTrim(txtrecode.Text) & RTrim(code)
        End If
        i = i + 1
        Loop
End Sub