' Project SQLExamples

' Display table resulting from an SQL statement
' in DataGrid control.

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 Label2 As System.Windows.Forms.Label
    Friend WithEvents cboSQL As System.Windows.Forms.ComboBox
    Friend WithEvents dgGroceries As System.Windows.Forms.DataGrid
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.Label2 = New System.Windows.Forms.Label
        Me.cboSQL = New System.Windows.Forms.ComboBox
        Me.dgGroceries = New System.Windows.Forms.DataGrid
        CType(Me.dgGroceries, System.ComponentModel.ISupportInitialize).BeginInit()
        Me.SuspendLayout()
        '
        'Label2
        '
        Me.Label2.Font = New System.Drawing.Font("Microsoft Sans Serif", 9.75!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.Label2.Location = New System.Drawing.Point(16, 16)
        Me.Label2.Name = "Label2"
        Me.Label2.Size = New System.Drawing.Size(104, 16)
        Me.Label2.TabIndex = 3
        Me.Label2.Text = "SQL Statement"
        '
        'cboSQL
        '
        Me.cboSQL.Font = New System.Drawing.Font("Microsoft Sans Serif", 9.75!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.cboSQL.Location = New System.Drawing.Point(136, 16)
        Me.cboSQL.Name = "cboSQL"
        Me.cboSQL.Size = New System.Drawing.Size(592, 24)
        Me.cboSQL.TabIndex = 8
        '
        'dgGroceries
        '
        Me.dgGroceries.DataMember = ""
        Me.dgGroceries.HeaderForeColor = System.Drawing.SystemColors.ControlText
        Me.dgGroceries.Location = New System.Drawing.Point(24, 64)
        Me.dgGroceries.Name = "dgGroceries"
        Me.dgGroceries.Size = New System.Drawing.Size(616, 272)
        Me.dgGroceries.TabIndex = 9
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(752, 358)
        Me.Controls.Add(Me.dgGroceries)
        Me.Controls.Add(Me.cboSQL)
        Me.Controls.Add(Me.Label2)
        Me.Name = "Form1"
        Me.Text = "Groceries5 Example"
        CType(Me.dgGroceries, System.ComponentModel.ISupportInitialize).EndInit()
        Me.ResumeLayout(False)

    End Sub

#End Region

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

        ' Load SQL statements into combo box.
        cboSQL.Items.Add("SELECT * FROM GroceryList")
        cboSQL.Items.Add("SELECT ItemName, Price FROM GroceryList")
        cboSQL.Items.Add("SELECT ItemName, Code, Price FROM GroceryList " & _
            "WHERE 2.00 < Price")
        cboSQL.Items.Add("SELECT ItemName, Code, Price FROM GroceryList " & _
            "WHERE 2.00 < Price And Price <= 3.00")
        cboSQL.Items.Add("SELECT ItemName, Code, Price FROM GroceryList " & _
            "WHERE 2.00 < Price And IsOnSale=True")
        cboSQL.Items.Add("SELECT ItemName, Code, Price, IsOnSale FROM GroceryList " & _
            "WHERE ItemName = 'Chicken Wings'")

        ' 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

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

        ' Create DataSet object.
        ds = New DataSet
    End Sub

    Private Sub cboName_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cboSQL.SelectedIndexChanged

        ' Obtain SQL statement from combo box.
        Dim sql As String = cboSQL.SelectedItem

        ' Don't forget single quotes around SQL constant string.
        sc.CommandText = sql

        ' Clear dataset.
        ds.Clear()

        ' Fill dataset from data adapter using new SQL statement.
        nRows = da.Fill(ds, "GroceryList")

        ' Bind dataset to datagrid.
        dgGroceries.DataSource = ds.Tables(0)
    End Sub
End Class