frmtest.frm

LZW数据压缩算法

VERSION 5.00
Begin VB.Form frmTest 
   AutoRedraw      =   -1  'True
   BorderStyle     =   1  'Fixed Single
   Caption         =   "LZW Compression - by Asgeir B. Ingvarsson"
   ClientHeight    =   4650
   ClientLeft      =   45
   ClientTop       =   330
   ClientWidth     =   7815
   LinkTopic       =   "Form1"
   MaxButton       =   0   'False
   MinButton       =   0   'False
   ScaleHeight     =   4650
   ScaleWidth      =   7815
   StartUpPosition =   3  'Windows Default
   Begin VB.TextBox txtYourString 
      Height          =   285
      Left            =   360
      Locked          =   -1  'True
      MaxLength       =   80
      TabIndex        =   16
      Text            =   "TxtYourString"
      Top             =   1005
      Width           =   5655
   End
   Begin VB.OptionButton optString 
      Height          =   375
      Index           =   2
      Left            =   120
      TabIndex        =   15
      Top             =   960
      Width           =   255
   End
   Begin VB.CommandButton cmdExit 
      Caption         =   "&Exit"
      Height          =   375
      Left            =   6480
      TabIndex        =   14
      Top             =   1080
      Width           =   1215
   End
   Begin VB.Frame fme 
      Caption         =   "Results"
      Height          =   2655
      Left            =   120
      TabIndex        =   3
      Top             =   1800
      Width           =   7575
      Begin VB.Label lblResult 
         BackColor       =   &H80000009&
         BorderStyle     =   1  'Fixed Single
         Caption         =   "lblresult"
         Height          =   285
         Index           =   5
         Left            =   1920
         TabIndex        =   18
         Top             =   2160
         Width           =   3135
      End
      Begin VB.Label lblText 
         AutoSize        =   -1  'True
         Caption         =   "Time Taken:"
         Height          =   195
         Index           =   5
         Left            =   240
         TabIndex        =   17
         Top             =   2160
         Width           =   900
      End
      Begin VB.Label lblResult 
         BackColor       =   &H80000009&
         BorderStyle     =   1  'Fixed Single
         Caption         =   "lblresult"
         Height          =   285
         Index           =   4
         Left            =   1920
         TabIndex        =   13
         Top             =   1800
         Width           =   3135
      End
      Begin VB.Label lblResult 
         BackColor       =   &H80000009&
         BorderStyle     =   1  'Fixed Single
         Caption         =   "lblresult"
         Height          =   285
         Index           =   3
         Left            =   1920
         TabIndex        =   12
         Top             =   1440
         Width           =   3135
      End
      Begin VB.Label lblResult 
         BackColor       =   &H80000009&
         BorderStyle     =   1  'Fixed Single
         Caption         =   "lblresult"
         Height          =   285
         Index           =   2
         Left            =   1920
         TabIndex        =   11
         Top             =   1080
         Width           =   3135
      End
      Begin VB.Label lblResult 
         BackColor       =   &H80000009&
         BorderStyle     =   1  'Fixed Single
         Caption         =   "lblresult"
         Height          =   285
         Index           =   1
         Left            =   1920
         TabIndex        =   10
         Top             =   720
         Width           =   5535
      End
      Begin VB.Label lblResult 
         BackColor       =   &H80000009&
         BorderStyle     =   1  'Fixed Single
         Caption         =   "lblresult"
         Height          =   285
         Index           =   0
         Left            =   1920
         TabIndex        =   9
         Top             =   360
         Width           =   5535
      End
      Begin VB.Label lblText 
         AutoSize        =   -1  'True
         Caption         =   "Compression Ratio:"
         Height          =   195
         Index           =   4
         Left            =   240
         TabIndex        =   8
         Top             =   1800
         Width           =   1365
      End
      Begin VB.Label lblText 
         AutoSize        =   -1  'True
         Caption         =   "Compressed Size:"
         Height          =   195
         Index           =   3
         Left            =   240
         TabIndex        =   7
         Top             =   1440
         Width           =   1260
      End
      Begin VB.Label lblText 
         AutoSize        =   -1  'True
         Caption         =   "Input Size:"
         Height          =   195
         Index           =   2
         Left            =   240
         TabIndex        =   6
         Top             =   1080
         Width           =   750
      End
      Begin VB.Label lblText 
         AutoSize        =   -1  'True
         Caption         =   "Compressed String:"
         Height          =   195
         Index           =   1
         Left            =   240
         TabIndex        =   5
         Top             =   720
         Width           =   1365
      End
      Begin VB.Label lblText 
         AutoSize        =   -1  'True
         Caption         =   "Input String:"
         Height          =   195
         Index           =   0
         Left            =   240
         TabIndex        =   4
         Top             =   360
         Width           =   855
      End
   End
   Begin VB.OptionButton optString 
      Caption         =   "Repeated string of text... Repeated string of text... Repeated string of text... Repeated....."
      Height          =   375
      Index           =   1
      Left            =   120
      TabIndex        =   2
      Top             =   120
      Width           =   7095
   End
   Begin VB.CommandButton cmdCompress 
      Caption         =   "&Compress"
      Height          =   375
      Left            =   6480
      TabIndex        =   1
      Top             =   600
      Width           =   1215
   End
   Begin VB.OptionButton optString 
      Caption         =   "The quick brown fox jumped over the lazy dog."
      Height          =   495
      Index           =   0
      Left            =   120
      TabIndex        =   0
      Top             =   480
      Value           =   -1  'True
      Width           =   3975
   End
End
Attribute VB_Name = "frmTest"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit
Private lSelected As Byte

Private Sub CmdCompress_Click()

  Dim InputString As String
  Dim CompString As String
  Dim ExpString As String
  Dim ElapsedTime As Single


  Screen.MousePointer = vbDefault

  If lSelected <> 2 Then
    InputString = optString(lSelected).Caption
  Else
    InputString = txtYourString
  End If
  
  ElapsedTime = Timer
  CompString = Deflate(InputString) 'Compress
  ExpString = Inflate(CompString) 'Uncompress
  
  lblResult(0) = ExpString
  lblResult(1) = CompString
  lblResult(2) = Len(ExpString)
  lblResult(3) = Len(CompString)
  lblResult(4) = (100 - 100 * Len(CompString) \ Len(ExpString)) & "%"
  lblResult(5) = Format(Timer - ElapsedTime, "0.00") & " seconds"
  
  Screen.MousePointer = vbDefault
End Sub

Private Sub cmdExit_Click()
  Unload Me
End Sub

Private Sub Form_Load()
  Dim c As Byte
  
  For c = 0 To lblResult.UBound
    lblResult(c).Caption = ""
  Next
  
  txtYourString = "<Enter Your String Here>"
End Sub

Private Sub Form_Unload(Cancel As Integer)
  End
End Sub

Private Sub optString_Click(Index As Integer)
  lSelected = Index
  
  If lSelected <> 2 Then
    txtYourString.Locked = True
  Else
    txtYourString.Locked = False
  End If
End Sub

Private Sub txtYourString_GotFocus()
  With txtYourString
    .SelStart = 0
    .SelLength = Len(txtYourString)
  End With
End Sub

Private Sub txtYourString_KeyPress(KeyAscii As Integer)
  optString(2).Value = True
End Sub