frmmenu.vb

本系统利用vb.net做为前台开发工具

    Me.btnExt.Name = "btnExt"
    Me.btnExt.Size = New System.Drawing.Size(88, 40)
    Me.btnExt.TabIndex = 4
    Me.btnExt.Text = "退  出"
    '
    'frmMenu
    '
    Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
    Me.CancelButton = Me.btnExt
    Me.ClientSize = New System.Drawing.Size(680, 496)
    Me.Controls.Add(Me.btnExt)
    Me.Controls.Add(Me.btnSav)
    Me.Controls.Add(Me.btnEdt)
    Me.Controls.Add(Me.btnDel)
    Me.Controls.Add(Me.btnAdd)
    Me.Controls.Add(Me.grbMenu)
    Me.Controls.Add(Me.dgdMenu)
    Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None
    Me.Icon = CType(resources.GetObject("$this.Icon"), System.Drawing.Icon)
    Me.MaximizeBox = False
    Me.Name = "frmMenu"
    Me.Text = "菜谱管理"
    Me.WindowState = System.Windows.Forms.FormWindowState.Maximized
    CType(Me.dgdMenu, System.ComponentModel.ISupportInitialize).EndInit()
    Me.grbMenu.ResumeLayout(False)
    Me.ResumeLayout(False)

  End Sub

#End Region
    '用于区分是对增加进行保存还是对编辑进行保存
    Dim SavAsAdd As Boolean
    '创建DB类的对象
    Dim odb As New DB.DB
    '定义字符串变量，用于保存数据表操作的SQL语句
    Dim sqlSel As String
    Private Sub frmMenu_Load(ByVal sender As System.Object, ByVal e As _
                System.EventArgs) Handles MyBase.Load
        '定义变量用于保存窗体的最大高度和宽度
        Dim m, n As Integer
        sqlSel = "select id as 编号,name as 菜名,status as 是否可用,price " & _
                "as 价格,type as 类型,memo as 说明 from menu"
        Me.WindowState = FormWindowState.Maximized
        '记录窗体的最大高度和宽度
        m = Me.Height
        n = Me.Width
        Me.WindowState = FormWindowState.Normal
        '设置窗体的大小和位置
        Me.Width = n
        Me.Height = m
        Me.Top = 0
        Me.Left = 0
        '设置窗体中各个控件的位置和大小
        dgdMenu.Left = 0
        dgdMenu.Top = 0
        dgdMenu.Width = Me.Width
        dgdMenu.Height = 2 * Me.Height / 5
        dgdMenu.RowHeaderWidth = 5
        dgdMenu.PreferredColumnWidth = (Me.Width - 35) / 6
        grbMenu.Left = 20
        grbMenu.Top = dgdMenu.Height + 20
        grbMenu.Width = Me.Width - 40
        grbMenu.Height = 2 * Me.Height / 5
        btnAdd.Left = 250
        btnAdd.Top = dgdMenu.Height + grbMenu.Height + 50
        btnAdd.Height = 40
        btnAdd.Width = 80
        btnDel.Left = 350
        btnDel.Top = dgdMenu.Height + grbMenu.Height + 50
        btnDel.Height = 40
        btnDel.Width = 80
        btnEdt.Left = 450
        btnEdt.Top = dgdMenu.Height + grbMenu.Height + 50
        btnEdt.Height = 40
        btnEdt.Width = 80
        btnSav.Left = 550
        btnSav.Top = dgdMenu.Height + grbMenu.Height + 50
        btnSav.Height = 40
        btnSav.Width = 80
        btnExt.Left = 650
        btnExt.Top = dgdMenu.Height + grbMenu.Height + 50
        btnExt.Height = 40
        btnExt.Width = 80
        '设置表格的数据源
        dgdMenu.DataSource = odb.CreateDataTable(sqlSel)
        '设置各个控件的状态
        FreshFrm(0)
    End Sub
    Private Sub FreshFrm(ByVal n As Integer)
        '设置增加、删除和编辑操作可用
        btnAdd.Enabled = True
        btnDel.Enabled = True
        btnEdt.Enabled = True
        '设置保存功能不可用
        btnSav.Enabled = False
        '设置记录的详细信息不可编辑
        txtNo.ReadOnly = True
        txtName.ReadOnly = True
        txtPrice.ReadOnly = True
        txtMemo.ReadOnly = True
        cmbStatus.Enabled = False
        cmbType.Enabled = False
        '设置各个控件中的值
        txtNo.Text = dgdMenu.Item(n, 0)
        txtName.Text = dgdMenu.Item(n, 1)
        cmbStatus.Text = IIf(dgdMenu.Item(n, 2) = "Y", "可用", "不可")
        txtPrice.Text = dgdMenu.Item(n, 3)
        cmbType.Text = dgdMenu.Item(n, 4)
        txtMemo.Text = dgdMenu.Item(n, 5)
    End Sub


    Private Sub dgdMenu_CurrentCellChanged(ByVal sender As Object, ByVal e _
                As System.EventArgs) Handles dgdMenu.CurrentCellChanged
        '当当前单元格变化时重新刷新窗体中控件值
        FreshFrm(dgdMenu.CurrentCell.RowNumber)
    End Sub


    Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As _
                System.EventArgs) Handles btnAdd.Click
        '设置文本框和组合框可用并赋初值
        txtName.ReadOnly = False
        txtName.Text = ""
        txtNo.ReadOnly = False
        txtNo.Text = ""
        txtPrice.ReadOnly = False
        txtPrice.Text = ""
        txtMemo.ReadOnly = False
        txtMemo.Text = ""
        cmbStatus.Enabled = True
        cmbType.Enabled = True
        cmbStatus.Text = "可用"
        cmbType.Text = "热菜"
        '增加操作时增加、删除和修改操作都不可用
        '增加操作时保存操作可用
        btnAdd.Enabled = False
        btnDel.Enabled = False
        btnEdt.Enabled = False
        btnSav.Enabled = True
        '设置增加操作标志
        SavAsAdd = True
    End Sub


    Private Sub btnEdt_Click(ByVal sender As System.Object, ByVal e As _
                System.EventArgs) Handles btnEdt.Click
        '设置文本框和组合框可用
        txtName.ReadOnly = False
        txtPrice.ReadOnly = False
        txtMemo.ReadOnly = False
        cmbStatus.Enabled = True
        cmbType.Enabled = True
        '编辑操作时增加、删除和修改操作都不可用
        '编辑操作时保存操作可用
        btnAdd.Enabled = False
        btnDel.Enabled = False
        btnEdt.Enabled = False
        btnSav.Enabled = True
        SavAsAdd = False
    End Sub



    Private Sub btnSav_Click(ByVal sender As System.Object, ByVal e As _
            System.EventArgs) Handles btnSav.Click
        '对增加操作进行保存
        If SavAsAdd = True Then
            If txtName.Text = "" Then
                '新增加的记录必须有菜肴名称
                MsgBox("菜肴的名称是需要要输入的！", MsgBoxStyle.Exclamation)
                txtName.Focus()
                Exit Sub
            Else
                If txtNo.Text = "" Then
                    '新增加的记录必须有菜肴编号
                    MsgBox("菜肴的编号是需要要输入的！", MsgBoxStyle.Exclamation)
                    txtNo.Focus()
                    Exit Sub
                Else
                    If txtPrice.Text = "" Then
                        '新增加的记录必须有菜肴价格
                        MsgBox("价格字段是需要要输入的！", MsgBoxStyle.Exclamation)
                        txtPrice.Focus()
                        Exit Sub
                    Else
                        '输入检测无误后可以提交数据
                        Try
                            Dim strSql = "insert into Menu  " & "values ('" & _
                                Trim(txtNo.Text) & "','" & Trim(txtName.Text) & "','" & _
                                IIf(cmbStatus.Text = "可用", "Y", "N") & _
                                "',convert(smallmoney," & "'" & Trim(txtPrice.Text) & _
                                "'),'" & Trim(cmbType.Text) & "','" & Trim(txtMemo.Text) & "')"
                            '按照顺序将用户输入的数据插入到相应的字段中
                            '调用DB类中方法进行数据表更新
                            odb.UpdateDataBase(strsql)
                            'DataGrid重新检索更新后的数据
                            dgdMenu.DataSource = odb.CreateDataTable(sqlSel)
                            MsgBox("增加操作成功！", MsgBoxStyle.Information)
                        Catch mm As Exception
                            '捕捉异常
                            MsgBox(mm.Message)
                            Exit Sub
                        End Try
                    End If
                End If
            End If
        Else
            '对编辑操作进行保存
            If txtName.Text = "" Then
                '编辑的记录必须有菜肴名称
                MsgBox("菜肴的名称是需要要输入的！", MsgBoxStyle.Exclamation)
                txtName.Focus()
                Exit Sub
            Else
                If txtPrice.Text = "" Then
                    '编辑的记录必须有菜肴价格
                    MsgBox("价格字段是需要要输入的！", MsgBoxStyle.Exclamation)
                    txtPrice.Focus()
                    Exit Sub
                Else
                    '输入检测无误后可以提交数据
                    Try
                        Dim strSql As String = "update  menu set Name='" & Trim(txtName.Text) _
                            & "',Status='" & IIf(cmbStatus.Text = "可用", "Y", "N") & _
                            "',Price =convert(smallmoney,'" & Trim(txtPrice.Text) & _
                            "'),Type='" & cmbType.Text & "',Memo='" & Trim(txtMemo.Text) _
                            & "'  where ID='" & Trim(txtNo.Text) & "'"
                        '按照顺序将用户输入的数据插入到相应的字段中
                        '调用DB类中方法进行数据表更新
                        odb.UpdateDataBase(strsql)
                        'DataGrid重新检索更新后的数据
                        dgdMenu.DataSource = odb.CreateDataTable(sqlSel)
                        MsgBox("编辑操作成功！", MsgBoxStyle.Information)
                    Catch mm As Exception
                        '  捕捉异常
                        MsgBox(mm.Message)
                        Exit Sub
                    End Try
                End If
            End If
        End If
        '刷新详细信息
        FreshFrm(dgdMenu.CurrentRowIndex)
    End Sub



    Private Sub btnDel_Click(ByVal sender As System.Object, ByVal e As _
                System.EventArgs) Handles btnDel.Click
        '确认是否删除，如果用户选择Yes，则进行删除处理；否则，不进行任何操作
        If MsgBox("删除的记录不能恢复，确定要删除么？", MsgBoxStyle.Question _
            + MsgBoxStyle.YesNo) = MsgBoxResult.Yes Then
            Try
                '以编号为关键字删除Menu数据表中记录
                Dim strDel As String = "delete from menu where ID = '" & _
                    Trim(txtNo.Text) & "'"
                '调用DB类中UpdateDateBase方法执行指定的操作
                odb.UpdateDataBase(strDel)
                'DataGrid表格重新检索数据
                dgdMenu.DataSource = odb.CreateDataTable(sqlSel)
                MsgBox("删除成功！", MsgBoxStyle.Information)
            Catch mm As Exception
                '异常处理
                MsgBox(mm.Message)
                Exit Sub
            End Try
        End If
        '刷新详细信息
        FreshFrm(0)
    End Sub
    Private Sub btnExt_Click(ByVal sender As System.Object, ByVal e As _
                System.EventArgs) Handles btnExt.Click
        Me.Close()
    End Sub

    Private Sub txtPrice_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtPrice.TextChanged
        If Not (Val(Trim(txtPrice.Text) > 0)) Then
            MsgBox("价格必须是正数！", MsgBoxStyle.Exclamation)
            txtPrice.Focus()
            '选中优惠金额文本框中数字部分
            txtPrice.Select(0, Len(txtPrice.Text))
            Exit Sub
        End If
    End Sub
End Class