form1.vb

编程之道VB.NETt程序设计入门-589M.zip

Public Class Form1
    Inherits System.Windows.Forms.Form

#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

    '窗体重写处置以清理组件列表。
    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 txtOperand1 As System.Windows.Forms.TextBox
    Friend WithEvents btnCalculate As System.Windows.Forms.Button
    Friend WithEvents chkSave As System.Windows.Forms.CheckBox
    Friend WithEvents lstResults As System.Windows.Forms.ListBox
    Friend WithEvents lblResult As System.Windows.Forms.Label
    Friend WithEvents cboOperator As System.Windows.Forms.ComboBox
    Friend WithEvents numupdOperand2 As System.Windows.Forms.NumericUpDown
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.txtOperand1 = New System.Windows.Forms.TextBox()
        Me.cboOperator = New System.Windows.Forms.ComboBox()
        Me.lstResults = New System.Windows.Forms.ListBox()
        Me.numupdOperand2 = New System.Windows.Forms.NumericUpDown()
        Me.btnCalculate = New System.Windows.Forms.Button()
        Me.chkSave = New System.Windows.Forms.CheckBox()
        Me.lblResult = New System.Windows.Forms.Label()
        CType(Me.numupdOperand2, System.ComponentModel.ISupportInitialize).BeginInit()
        Me.SuspendLayout()
        '
        'txtOperand1
        '
        Me.txtOperand1.Location = New System.Drawing.Point(8, 16)
        Me.txtOperand1.Name = "txtOperand1"
        Me.txtOperand1.Size = New System.Drawing.Size(96, 21)
        Me.txtOperand1.TabIndex = 0
        Me.txtOperand1.Text = ""
        '
        'cboOperator
        '
        Me.cboOperator.Items.AddRange(New Object() {"+", "-", "*", "/"})
        Me.cboOperator.Location = New System.Drawing.Point(112, 16)
        Me.cboOperator.Name = "cboOperator"
        Me.cboOperator.Size = New System.Drawing.Size(80, 20)
        Me.cboOperator.TabIndex = 1
        '
        'lstResults
        '
        Me.lstResults.ItemHeight = 12
        Me.lstResults.Location = New System.Drawing.Point(200, 160)
        Me.lstResults.Name = "lstResults"
        Me.lstResults.Size = New System.Drawing.Size(112, 88)
        Me.lstResults.TabIndex = 2
        '
        'numupdOperand2
        '
        Me.numupdOperand2.Location = New System.Drawing.Point(200, 16)
        Me.numupdOperand2.Name = "numupdOperand2"
        Me.numupdOperand2.Size = New System.Drawing.Size(112, 21)
        Me.numupdOperand2.TabIndex = 3
        '
        'btnCalculate
        '
        Me.btnCalculate.Location = New System.Drawing.Point(224, 64)
        Me.btnCalculate.Name = "btnCalculate"
        Me.btnCalculate.Size = New System.Drawing.Size(88, 24)
        Me.btnCalculate.TabIndex = 4
        Me.btnCalculate.Text = "计算"
        '
        'chkSave
        '
        Me.chkSave.Location = New System.Drawing.Point(136, 64)
        Me.chkSave.Name = "chkSave"
        Me.chkSave.Size = New System.Drawing.Size(80, 24)
        Me.chkSave.TabIndex = 5
        Me.chkSave.Text = "保存结果"
        '
        'lblResult
        '
        Me.lblResult.Location = New System.Drawing.Point(208, 112)
        Me.lblResult.Name = "lblResult"
        Me.lblResult.Size = New System.Drawing.Size(96, 24)
        Me.lblResult.TabIndex = 6
        Me.lblResult.Text = "计算结果"
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.ClientSize = New System.Drawing.Size(320, 254)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.lblResult, Me.chkSave, Me.btnCalculate, Me.numupdOperand2, Me.lstResults, Me.cboOperator, Me.txtOperand1})
        Me.Name = "Form1"
        Me.Text = "Form1"
        CType(Me.numupdOperand2, System.ComponentModel.ISupportInitialize).EndInit()
        Me.ResumeLayout(False)

    End Sub

#End Region

    Private Sub btnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click
        Dim iOperand1 As Integer
        Dim iOperand2 As Integer
        Dim iResult As Integer
        Dim cOperator As Char

        Try
            iOperand1 = CInt(txtOperand1.Text)      '取得第一个运算数的值
            iOperand2 = numupdOperand2.Value         '取得第二个运算数的值
            cOperator = cboOperator.Text            '取得运算符

            Select Case cOperator                   '进行运算
                Case "+"
                    iResult = iOperand1 + iOperand2
                Case "-"
                    iResult = iOperand1 - iOperand2
                Case "*"
                    iResult = iOperand1 * iOperand2
                Case "/"
                    iResult = iOperand1 / iOperand2
                Case Else
                    MessageBox.Show("请选择运算符！")
                    Exit Sub
            End Select

            lblResult.Text = CStr(iResult)
            If chkSave.Checked Then lstResults.Items.Add(CStr(iResult))
        Catch ex As OverflowException
            lblResult.Text = "运算发生溢出！"
        Catch ex As InvalidCastException
            lblResult.Text = "运算参数无效！"
        Catch ex As Exception
            lblResult.Text = ex.Message
        End Try

    End Sub
End Class