form1.vb

来自「Visual Basic .NET程序设计教程源代码」· VB 代码 · 共 251 行

Public Class Form1
    Inherits System.Windows.Forms.Form
    Structure RecordType
        <VBFixedString(10)> Dim EmName As String
        <VBFixedString(16)> Dim Wunit As String
        Dim Age As Short
        Dim Salary As Short
    End Structure
    Dim recordvar As RecordType
    Dim recLen As Integer = Len(recordvar)
    Dim position As Integer
    Dim recordnumber As Long

#Region " Windows 窗体设计器生成的代码 "

    Public Sub New()
        MyBase.New()

        '该调用是 Windows 窗体设计器所必需的。
        InitializeComponent()

        '在 InitializeComponent() 调用之后添加任何初始化

    End Sub

    '窗体重写 dispose 以清理组件列表。
    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

    'Windows 窗体设计器所必需的
    Private components As System.ComponentModel.IContainer

    '注意: 以下过程是 Windows 窗体设计器所必需的
    '可以使用 Windows 窗体设计器修改此过程。
    '不要使用代码编辑器修改它。
    Friend WithEvents Button1 As System.Windows.Forms.Button
    Friend WithEvents Button2 As System.Windows.Forms.Button
    Friend WithEvents Button3 As System.Windows.Forms.Button
    Friend WithEvents Button4 As System.Windows.Forms.Button
    Friend WithEvents Button5 As System.Windows.Forms.Button
    Friend WithEvents Label1 As System.Windows.Forms.Label
    Friend WithEvents Label2 As System.Windows.Forms.Label
    Friend WithEvents Label3 As System.Windows.Forms.Label
    Friend WithEvents Label4 As System.Windows.Forms.Label
    Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
    Friend WithEvents TextBox2 As System.Windows.Forms.TextBox
    Friend WithEvents TextBox3 As System.Windows.Forms.TextBox
    Friend WithEvents TextBox4 As System.Windows.Forms.TextBox
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.Button1 = New System.Windows.Forms.Button
        Me.Button2 = New System.Windows.Forms.Button
        Me.Button3 = New System.Windows.Forms.Button
        Me.Button4 = New System.Windows.Forms.Button
        Me.Button5 = New System.Windows.Forms.Button
        Me.Label1 = New System.Windows.Forms.Label
        Me.Label2 = New System.Windows.Forms.Label
        Me.Label3 = New System.Windows.Forms.Label
        Me.Label4 = New System.Windows.Forms.Label
        Me.TextBox1 = New System.Windows.Forms.TextBox
        Me.TextBox2 = New System.Windows.Forms.TextBox
        Me.TextBox3 = New System.Windows.Forms.TextBox
        Me.TextBox4 = New System.Windows.Forms.TextBox
        Me.SuspendLayout()
        '
        'Button1
        '
        Me.Button1.Location = New System.Drawing.Point(48, 104)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New System.Drawing.Size(104, 23)
        Me.Button1.TabIndex = 0
        Me.Button1.Text = "显示前一个记录"
        '
        'Button2
        '
        Me.Button2.Location = New System.Drawing.Point(208, 104)
        Me.Button2.Name = "Button2"
        Me.Button2.Size = New System.Drawing.Size(104, 23)
        Me.Button2.TabIndex = 1
        Me.Button2.Text = "显示下一个记录"
        '
        'Button3
        '
        Me.Button3.Location = New System.Drawing.Point(16, 144)
        Me.Button3.Name = "Button3"
        Me.Button3.TabIndex = 2
        Me.Button3.Text = "打开文件"
        '
        'Button4
        '
        Me.Button4.Location = New System.Drawing.Point(144, 144)
        Me.Button4.Name = "Button4"
        Me.Button4.TabIndex = 3
        Me.Button4.Text = "修改数据"
        '
        'Button5
        '
        Me.Button5.Location = New System.Drawing.Point(280, 144)
        Me.Button5.Name = "Button5"
        Me.Button5.TabIndex = 4
        Me.Button5.Text = "退出程序"
        '
        'Label1
        '
        Me.Label1.Location = New System.Drawing.Point(24, 24)
        Me.Label1.Name = "Label1"
        Me.Label1.Size = New System.Drawing.Size(64, 23)
        Me.Label1.TabIndex = 5
        Me.Label1.Text = "姓名"
        '
        'Label2
        '
        Me.Label2.Location = New System.Drawing.Point(112, 24)
        Me.Label2.Name = "Label2"
        Me.Label2.Size = New System.Drawing.Size(56, 23)
        Me.Label2.TabIndex = 6
        Me.Label2.Text = "单位"
        '
        'Label3
        '
        Me.Label3.Location = New System.Drawing.Point(200, 24)
        Me.Label3.Name = "Label3"
        Me.Label3.Size = New System.Drawing.Size(64, 23)
        Me.Label3.TabIndex = 7
        Me.Label3.Text = "年龄"
        '
        'Label4
        '
        Me.Label4.Location = New System.Drawing.Point(296, 24)
        Me.Label4.Name = "Label4"
        Me.Label4.Size = New System.Drawing.Size(72, 23)
        Me.Label4.TabIndex = 8
        Me.Label4.Text = "工资"
        '
        'TextBox1
        '
        Me.TextBox1.Location = New System.Drawing.Point(16, 56)
        Me.TextBox1.Name = "TextBox1"
        Me.TextBox1.Size = New System.Drawing.Size(72, 21)
        Me.TextBox1.TabIndex = 9
        Me.TextBox1.Text = ""
        '
        'TextBox2
        '
        Me.TextBox2.Location = New System.Drawing.Point(104, 56)
        Me.TextBox2.Name = "TextBox2"
        Me.TextBox2.Size = New System.Drawing.Size(72, 21)
        Me.TextBox2.TabIndex = 10
        Me.TextBox2.Text = ""
        '
        'TextBox3
        '
        Me.TextBox3.Location = New System.Drawing.Point(192, 56)
        Me.TextBox3.Name = "TextBox3"
        Me.TextBox3.Size = New System.Drawing.Size(80, 21)
        Me.TextBox3.TabIndex = 11
        Me.TextBox3.Text = ""
        '
        'TextBox4
        '
        Me.TextBox4.Location = New System.Drawing.Point(288, 56)
        Me.TextBox4.Name = "TextBox4"
        Me.TextBox4.Size = New System.Drawing.Size(80, 21)
        Me.TextBox4.TabIndex = 12
        Me.TextBox4.Text = ""
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.ClientSize = New System.Drawing.Size(384, 189)
        Me.Controls.Add(Me.TextBox4)
        Me.Controls.Add(Me.TextBox3)
        Me.Controls.Add(Me.TextBox2)
        Me.Controls.Add(Me.TextBox1)
        Me.Controls.Add(Me.Label4)
        Me.Controls.Add(Me.Label3)
        Me.Controls.Add(Me.Label2)
        Me.Controls.Add(Me.Label1)
        Me.Controls.Add(Me.Button5)
        Me.Controls.Add(Me.Button4)
        Me.Controls.Add(Me.Button3)
        Me.Controls.Add(Me.Button2)
        Me.Controls.Add(Me.Button1)
        Me.Name = "Form1"
        Me.Text = "通过界面显示和修改随"
        Me.ResumeLayout(False)

    End Sub

#End Region
    Sub display()
        FileGet(1, recordvar, position)
        TextBox1.Text = recordvar.EmName
        TextBox2.Text = recordvar.Wunit
        TextBox3.Text = recordvar.Age
        TextBox4.Text = recordvar.Salary
    End Sub

    Private Sub Button3_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button3.Click
        FileOpen(1, "d:\temp\employee.txt", OpenMode.Random, OpenAccess.ReadWrite, , recLen)
        recordnumber = LOF(1) / Len(recordvar)
        position = 1
        display()
    End Sub

    Private Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        If position > 1 Then
            position -= 1
            display()
        ElseIf position = 1 Then
            MsgBox("这是第一个记录", , "")
        End If
    End Sub

    Private Sub Button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button2.Click
        Dim msg As String
        Dim resp As Short
        If position < recordnumber Then
            position = position + 1
            display()
        ElseIf position = recordnumber Then
            msg = "这是最后一个记录" + Chr(13) + Chr(10)
            msg = msg + "是否关闭文件？"
            resp = MsgBox(msg, 36, "请选择")
            If resp = 6 Then
                FileClose(1)
                End
            End If
        End If
    End Sub

    Private Sub Button4_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button4.Click
        recordvar.EmName = TextBox1.Text
        recordvar.Wunit = TextBox2.Text
        recordvar.Age = TextBox3.Text
        recordvar.Salary = TextBox4.Text
        FilePut(1, recordvar, position)
    End Sub

    Private Sub Button5_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button5.Click
        End
    End Sub
End Class