' Groceries5 Example

' Select items to display in a multiline textbox 
' according to whether the items are on sale.

Imports System.Data.OleDb
Public Class Form1
    Inherits System.Windows.Forms.Form

    Private c As OleDbConnection
    Private sc As OleDbCommand
    Private da As OleDbDataAdapter
    Private ds As DataSet
    Private nRows As Integer

#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

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

    '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.
    Friend WithEvents txtDisplay As System.Windows.Forms.TextBox
    Friend WithEvents btnAll As System.Windows.Forms.Button
    Friend WithEvents btnOnSale As System.Windows.Forms.Button
    Friend WithEvents btnNotOnSale As System.Windows.Forms.Button
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.txtDisplay = New System.Windows.Forms.TextBox
        Me.btnAll = New System.Windows.Forms.Button
        Me.btnOnSale = New System.Windows.Forms.Button
        Me.btnNotOnSale = New System.Windows.Forms.Button
        Me.SuspendLayout()
        '
        'txtDisplay
        '
        Me.txtDisplay.Font = New System.Drawing.Font("Courier New", 12.0!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.txtDisplay.Location = New System.Drawing.Point(8, 40)
        Me.txtDisplay.Multiline = True
        Me.txtDisplay.Name = "txtDisplay"
        Me.txtDisplay.Size = New System.Drawing.Size(328, 272)
        Me.txtDisplay.TabIndex = 0
        Me.txtDisplay.Text = ""
        '
        'btnAll
        '
        Me.btnAll.Location = New System.Drawing.Point(8, 8)
        Me.btnAll.Name = "btnAll"
        Me.btnAll.Size = New System.Drawing.Size(88, 24)
        Me.btnAll.TabIndex = 1
        Me.btnAll.Text = "Select All"
        '
        'btnOnSale
        '
        Me.btnOnSale.Location = New System.Drawing.Point(112, 8)
        Me.btnOnSale.Name = "btnOnSale"
        Me.btnOnSale.Size = New System.Drawing.Size(96, 24)
        Me.btnOnSale.TabIndex = 2
        Me.btnOnSale.Text = "Select On Sale"
        '
        'btnNotOnSale
        '
        Me.btnNotOnSale.Location = New System.Drawing.Point(224, 8)
        Me.btnNotOnSale.Name = "btnNotOnSale"
        Me.btnNotOnSale.Size = New System.Drawing.Size(112, 24)
        Me.btnNotOnSale.TabIndex = 3
        Me.btnNotOnSale.Text = "Select Not On Sale"
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(344, 318)
        Me.Controls.Add(Me.btnNotOnSale)
        Me.Controls.Add(Me.btnOnSale)
        Me.Controls.Add(Me.btnAll)
        Me.Controls.Add(Me.txtDisplay)
        Me.Name = "Form1"
        Me.Text = "GroceriesBinding Example"
        Me.ResumeLayout(False)

    End Sub

#End Region

    Private Sub Form1_Load(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles MyBase.Load

        ' Create and configure connection object.
        c = New OleDbConnection
        c.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
            "Data Source=c:\Database\Groceries.mdb"

        ' Create and configure command object.
        sc = c.CreateCommand()
        sc.CommandType = CommandType.Text
        sc.CommandText = "SELECT * FROM GroceryList"

        ' Create and configure data adapter object.
        da = New OleDbDataAdapter
        da.SelectCommand = sc

        ' Create and configure dataset object.
        ds = New DataSet
        nRows = da.Fill(ds, "GroceryList")

        ' Display all of the rows in the textbox.
        DisplayRows()

    End Sub

    Private Sub DisplayRows()

        ' Refill dataset.
        ds.Clear( )
        nRows = da.Fill(ds, "GroceryList")

        Dim output As String = "  Item Name     Code  Price  N" & _
            ControlChars.NewLine & "============    ====  =====  ==" & _
            ControlChars.NewLine

        Dim i As Integer
        For i = 0 To nRows - 1
            output &= String.Format("{0,-15}{1,6}{2,6:$#0.00}{3,4}", _
                ds.Tables(0).Rows(i).Item(1), _
                ds.Tables(0).Rows(i).Item(2), _
                ds.Tables(0).Rows(i).Item(3), _
                ds.Tables(0).Rows(i).Item(4)) + ControlChars.NewLine
        Next
        txtDisplay.Text = output
        txtDisplay.SelectionLength = 0
    End Sub

    Private Sub btnAll_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles btnAll.Click

        sc.CommandText = "SELECT * FROM GroceryList"
        DisplayRows()
    End Sub

    Private Sub btnOnSale_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles btnOnSale.Click

        sc.CommandText = "SELECT * FROM GroceryList WHERE IsOnSale=True"
        DisplayRows()
    End Sub

    Private Sub btnNotOnSale_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles btnNotOnSale.Click

        sc.CommandText = "SELECT * FROM GroceryList WHERE IsOnSale=False"
        DisplayRows()
    End Sub
End Class