Dan Appleman's Visual Bas…s Guide to the Win32 API/Dan.Applmans.Visual.Basic.5.0.Programmers.Guide.To.The.Win32.API.1997.Ziff-Davis.Press.CD/VB5PG32.mdf/articles/vbpj/source/llist1.frm

Visual Basic Form | 1996-01-29 | 10.8 KB | 317 lines

VERSION 4.00
Begin VB.Form frmMain
   Appearance      =   0  'Flat
   BackColor       =   &H80000005&
   Caption         =   "Linked List Example Program"
   ClientHeight    =   4095
   ClientLeft      =   1095
   ClientTop       =   1770
   ClientWidth     =   9780
   BeginProperty Font
      name            =   "MS Sans Serif"
      charset         =   1
      weight          =   700
      size            =   8.25
      underline       =   0   'False
      italic          =   0   'False
      strikethrough   =   0   'False
   EndProperty
   ForeColor       =   &H80000008&
   Height          =   4785
   Left            =   1035
   LinkTopic       =   "Form1"
   ScaleHeight     =   4095
   ScaleWidth      =   9780
   Top             =   1140
   Width           =   9900
   Begin VB.Frame Frame2
      Appearance      =   0  'Flat
      BackColor       =   &H80000005&
      Caption         =   "Display"
      ForeColor       =   &H80000008&
      Height          =   1215
      Left            =   2880
      TabIndex        =   5
      Top             =   2760
      Width           =   3555
      Begin VB.TextBox txtPerson
         Appearance      =   0  'Flat
         Height          =   315
         Left            =   1980
         TabIndex        =   8
         Text            =   "1"
         Top             =   780
         Width           =   675
      End
      Begin VB.OptionButton optDisplay
         Appearance      =   0  'Flat
         BackColor       =   &H80000005&
         Caption         =   "For Person"
         ForeColor       =   &H80000008&
         Height          =   315
         Index           =   1
         Left            =   120
         TabIndex        =   7
         Top             =   720
         Width           =   1275
      End
      Begin VB.OptionButton optDisplay
         Appearance      =   0  'Flat
         BackColor       =   &H80000005&
         Caption         =   "By Start Time"
         ForeColor       =   &H80000008&
         Height          =   315
         Index           =   0
         Left            =   120
         TabIndex        =   6
         Top             =   360
         Value           =   -1  'True
         Width           =   1575
      End
   End
   Begin VB.Frame Frame1
      Appearance      =   0  'Flat
      BackColor       =   &H80000005&
      Caption         =   "Implementation"
      ForeColor       =   &H80000008&
      Height          =   1215
      Left            =   120
      TabIndex        =   2
      Top             =   2760
      Width           =   2655
      Begin VB.OptionButton optImplementation
         Appearance      =   0  'Flat
         BackColor       =   &H80000005&
         Caption         =   "Array Based"
         ForeColor       =   &H80000008&
         Height          =   315
         Index           =   1
         Left            =   60
         TabIndex        =   4
         Top             =   720
         Width           =   1995
      End
      Begin VB.OptionButton optImplementation
         Appearance      =   0  'Flat
         BackColor       =   &H80000005&
         Caption         =   "Linked List Based"
         ForeColor       =   &H80000008&
         Height          =   315
         Index           =   0
         Left            =   60
         TabIndex        =   3
         Top             =   360
         Value           =   -1  'True
         Width           =   1935
      End
   End
   Begin VB.VScrollBar VScroll1
      Height          =   2655
      Left            =   9240
      Max             =   100
      Min             =   1
      TabIndex        =   1
      Top             =   60
      Value           =   1
      Width           =   315
   End
   Begin VB.PictureBox picDisplay
      Appearance      =   0  'Flat
      BackColor       =   &H80000005&
      BeginProperty Font
         name            =   "Courier New"
         charset         =   1
         weight          =   400
         size            =   8.25
         underline       =   0   'False
         italic          =   0   'False
         strikethrough   =   0   'False
      EndProperty
      ForeColor       =   &H80000008&
      Height          =   2655
      Left            =   120
      ScaleHeight     =   2625
      ScaleWidth      =   8985
      TabIndex        =   0
      Top             =   60
      Width           =   9015
   End
   Begin VB.Menu mnuTop1
      Caption         =   "Test"
      Begin VB.Menu mnuTest
         Caption         =   "Test Random Insert/Delete"
      End
      Begin VB.Menu mnuTestDisplay
         Caption         =   "Test Display"
      End
   End
Attribute VB_Name = "frmMain"
Attribute VB_Creatable = False
Attribute VB_Exposed = False
Option Explicit
' Set up the global variables and arrays
Private Sub Form_Load()
    Dim namecntr%
    ' Here we load the name array.  In this example, we
    ' are using a fixed set of names.  In a real program
    ' you would provide a mechanism to edit the name list.
    Open App.Path & "\" & "llnames.txt" For Input As #1
    For namecntr% = 1 To 20
        Input #1, NameArray$(namecntr%)
    Next namecntr%
    Close #1
    InitializeGlobals
End Sub
Private Sub mnuTest_Click()
    Dim starttime
    Dim counter%, idx%
    Dim se As ScheduleEntry
    Dim seLL As ScheduleEntryLL
    InitializeGlobals
    Screen.MousePointer = 11
    starttime = GetCurrentTime()
    ' First add 500 entries to get things started
    For counter% = 1 To 500
        If optImplementation(0).Value = 0 Then
            ' It's the array implementation
            GenerateRandom se.Start, se.Duration, se.Person
            se.Description = "Description for " & NameArray(se.Person)
            AddEntry se
        Else
            ' It's the linked list implementation
            GenerateRandom seLL.Start, seLL.Duration, seLL.Person
            seLL.Description = "Description for " & NameArray(seLL.Person)
            AddEntryLL seLL
        End If
    Next counter%
    ' Now another 500 miscellaneous insertions and deletions
    For counter% = 1 To 1000
        If optImplementation(0).Value = 0 Then
            ' It's the array implementation
            If Rnd < 0.5 Then
                GenerateRandom se.Start, se.Duration, se.Person
                se.Description = "Description for " & NameArray(se.Person)
                AddEntry se
            Else
                idx% = Int(Rnd * UBound(ScheduleARY) + 1)
                If ScheduleARY(idx%).Start <> 0 Then
                    DeleteEntry idx%
                End If
            End If
        Else
            ' It's the linked list implementation
            If Rnd < 0.5 Then
                ' It's the linked list implementation
                GenerateRandom seLL.Start, seLL.Duration, seLL.Person
                seLL.Description = "Description for " & NameArray(seLL.Person)
                AddEntryLL seLL
            Else
                idx% = Int(Rnd * UBound(ScheduleARY) + 1)
                If ScheduleLL(idx%).Start <> 0 Then
                    DeleteEntryLL idx%
                End If
            End If
        End If
    Next counter%
    Screen.MousePointer = 0
    MsgBox "Elapsed Time: " & GetCurrentTime() - starttime
    picDisplay.Refresh
End Sub
Private Sub mnuTestDisplay_Click()
    Dim starttime
    Dim counter%, idx%
    Screen.MousePointer = 11
    starttime = GetCurrentTime()
    ' Try displaying 100 times
    For counter% = 1 To 100
        picDisplay.Refresh
    Next counter%
    Screen.MousePointer = 0
    MsgBox "Elapsed Time: " & GetCurrentTime() - starttime
    picDisplay.Refresh
End Sub
Private Sub optDisplay_Click(Index As Integer)
    picDisplay.Refresh
End Sub
'   Display the array contents based on the requests
Private Sub picDisplay_Paint()
    Dim idx%, targetidx%, count%
    Dim personlmt%
    targetidx% = VScroll1.Value
    picDisplay.Cls  ' Clear the display
    If optImplementation(0).Value = 0 Then
        ' It's the ScheduleARY array
        If optDisplay(0).Value <> 0 Then
            VScroll1.Max = UBound(ScheduleARY)  ' Approximation
            ' Display by start time
            idx% = targetidx%
            Do While idx% < UBound(ScheduleARY)
                If ScheduleARY(idx%).Start = 0 Then Exit Do
                picDisplay.Print GetEntryDesc(idx%)
                If picDisplay.CurrentY > picDisplay.ScaleHeight Then Exit Do
                idx% = idx% + 1
            Loop
        Else
            ' Display by name
            personlmt% = Val(txtPerson.Text)
            VScroll1.Max = GetCount(personlmt%)
            idx% = 1
            count% = 0
            Do While idx% < UBound(ScheduleARY)
                If ScheduleARY(idx%).Start = 0 Then Exit Do
                If ScheduleARY(idx%).Person = personlmt% Then
                    count% = count% + 1 ' How many found?
                    If count% >= targetidx% Then
                        picDisplay.Print GetEntryDesc(idx%)
                        If picDisplay.CurrentY > picDisplay.ScaleHeight Then Exit Do
                        End If
                    End If
                idx% = idx% + 1
            Loop
        End If
    Else
        ' It's the ScheduleLL array (linked list)
        If optDisplay(0).Value <> 0 Then
            VScroll1.Max = UBound(ScheduleLL) ' Approximation
            ' Display by start time
            idx% = FirstTask
            count% = 0
            Do While idx% > 0
                count% = count% + 1
                If count% > targetidx% Then
                    picDisplay.Print GetEntryDescLL(idx%)
                    If picDisplay.CurrentY > picDisplay.ScaleHeight Then Exit Do
                End If
                idx% = ScheduleLL(idx%).StartLink.Forward
            Loop
        Else
            ' Display by name
            personlmt% = Val(txtPerson.Text)
            VScroll1.Max = GetCountLL(personlmt%)
            idx% = FirstPerson(personlmt%)
            count% = 0 ' Tracks how many to skip
            Do While idx% > 0
                count% = count% + 1 ' How many found?
                If count% >= targetidx% Then
                    picDisplay.Print GetEntryDescLL(idx%)
                    If picDisplay.CurrentY > picDisplay.ScaleHeight Then Exit Do
                End If
                idx% = ScheduleLL(idx%).PersonLink.Forward
            Loop
        End If


        ' It's the linked list array
    End If

End Sub
Private Sub txtPerson_Change()
    picDisplay.Refresh
End Sub
Private Sub VScroll1_Change()
    picDisplay.Refresh
End Sub
Private Sub VScroll1_Scroll()
    picDisplay.Refresh
End Sub