linearsearchtest.vb

VB.net数据结构演示算法

' Fig. 7.13: LinearSearchTest.vb
' Linear search of an array

Public Class FrmLinearSearchTest
   Inherits System.Windows.Forms.Form

#Region " Windows Form Designer generated code "

   Public Sub New()
      MyBase.New()

      'This call is required by the Windows Form Designer.
      InitializeComponent()

      'Add any initialization after the InitializeComponent() call

   End Sub

   'Form overrides dispose to clean up the component list.
   Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
      If disposing Then
         If Not (components Is Nothing) Then
            components.Dispose()
         End If
      End If
      MyBase.Dispose(disposing)
   End Sub
   Friend WithEvents cmdSearch As System.Windows.Forms.Button
   Friend WithEvents cmdCreate As System.Windows.Forms.Button

   Friend WithEvents lblEnter As System.Windows.Forms.Label
   Friend WithEvents lblResult As System.Windows.Forms.Label

   Friend WithEvents txtInput As System.Windows.Forms.TextBox
   Friend WithEvents txtData As System.Windows.Forms.TextBox

   'Required by the Windows Form Designer
   Private components As System.ComponentModel.Container

   'NOTE: The following procedure is required by the Windows Form Designer
   'It can be modified using the Windows Form Designer.  
   'Do not modify it using the code editor.
   <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
      Me.txtData = New System.Windows.Forms.TextBox()
      Me.lblEnter = New System.Windows.Forms.Label()
      Me.cmdCreate = New System.Windows.Forms.Button()
      Me.txtInput = New System.Windows.Forms.TextBox()
      Me.cmdSearch = New System.Windows.Forms.Button()
      Me.lblResult = New System.Windows.Forms.Label()
      Me.SuspendLayout()
      '
      'txtData
      '
      Me.txtData.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
      Me.txtData.Location = New System.Drawing.Point(8, 48)
      Me.txtData.Multiline = True
      Me.txtData.Name = "txtData"
      Me.txtData.ScrollBars = System.Windows.Forms.ScrollBars.Vertical
      Me.txtData.Size = New System.Drawing.Size(256, 112)
      Me.txtData.TabIndex = 4
      Me.txtData.Text = ""
      '
      'lblEnter
      '
      Me.lblEnter.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
      Me.lblEnter.Location = New System.Drawing.Point(8, 8)
      Me.lblEnter.Name = "lblEnter"
      Me.lblEnter.Size = New System.Drawing.Size(200, 24)
      Me.lblEnter.TabIndex = 2
      Me.lblEnter.Text = "Enter Integer Search Key.:"
      Me.lblEnter.TextAlign = System.Drawing.ContentAlignment.BottomCenter
      '
      'cmdCreate
      '
      Me.cmdCreate.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
      Me.cmdCreate.Location = New System.Drawing.Point(8, 200)
      Me.cmdCreate.Name = "cmdCreate"
      Me.cmdCreate.Size = New System.Drawing.Size(88, 40)
      Me.cmdCreate.TabIndex = 2
      Me.cmdCreate.Text = "Create Data"
      '
      'txtInput
      '
      Me.txtInput.Cursor = System.Windows.Forms.Cursors.IBeam
      Me.txtInput.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
      Me.txtInput.Location = New System.Drawing.Point(216, 8)
      Me.txtInput.Name = "txtInput"
      Me.txtInput.Size = New System.Drawing.Size(48, 26)
      Me.txtInput.TabIndex = 3
      Me.txtInput.Text = ""
      Me.txtInput.TextAlign = System.Windows.Forms.HorizontalAlignment.Right
      '
      'cmdSearch
      '
      Me.cmdSearch.Enabled = False
      Me.cmdSearch.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
      Me.cmdSearch.Location = New System.Drawing.Point(176, 200)
      Me.cmdSearch.Name = "cmdSearch"
      Me.cmdSearch.Size = New System.Drawing.Size(88, 40)
      Me.cmdSearch.TabIndex = 0
      Me.cmdSearch.Text = "Search"
      '
      'lblResult
      '
      Me.lblResult.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
      Me.lblResult.Location = New System.Drawing.Point(8, 160)
      Me.lblResult.Name = "lblResult"
      Me.lblResult.Size = New System.Drawing.Size(256, 32)
      Me.lblResult.TabIndex = 6
      '
      'FrmLinearSearchTest
      '
      Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
      Me.ClientSize = New System.Drawing.Size(272, 253)
      Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.cmdCreate, Me.lblResult, Me.txtData, Me.txtInput, Me.lblEnter, Me.cmdSearch})
      Me.Name = "FrmLinearSearchTest"
      Me.Text = "Linear Search"
      Me.ResumeLayout(False)

   End Sub

#End Region

   Dim array1 As Integer() = New Integer(19) {}

   ' creates random data 
   Private Sub cmdCreate_Click(ByVal sender As System.Object, _
      ByVal e As System.EventArgs) Handles cmdCreate.Click

      Dim output As String
      Dim randomNumber As Random = New Random()
      Dim i As Integer

      output = "Index" & vbTab & "Value" & vbCrLf

      ' creates string containing 11 random numbers
      For i = 0 To array1.GetUpperBound(0)
         array1(i) = randomNumber.Next(1000)
         output &= i & vbTab & array1(i) & vbCrLf
      Next

      txtData.Text = output    ' displays numbers 
      txtInput.Text = ""       ' clear search key text box
      cmdSearch.Enabled = True ' enable search button
   End Sub ' cmdCreate_Click

   ' searches key of element 
   Private Sub cmdSearch_Click(ByVal sender As System.Object, _
      ByVal e As System.EventArgs) Handles cmdSearch.Click

      ' if search key text box is empty, display 
      ' message and exit procedure
      If txtInput.Text = "" Then
         MessageBox.Show("You must enter a search key.")
         Exit Sub
      End If

      Dim searchKey As Integer = Convert.ToInt32(txtInput.Text)
      Dim element As Integer = LinearSearch(searchKey, array1)

      If element <> -1 Then
         lblResult.Text = "Found Value in index " & element
      Else
         lblResult.Text = "Value Not Found"
      End If

   End Sub ' cmdSearch_Click

End Class ' FrmLinearSearch

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' * (C) Copyright 2002 by Deitel & Associates, Inc.           *
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