VB.Net程序设计：ADO.Net读取Access表架构

程序只是记录而已，还没有完成。

请不要模仿。

Imports System.Data
Imports System.Data.OleDb

Public Class Form1

    Dim ConnStr As String = String.Format("Provider=Microsoft.Jet.OLEDB.4.0; Data Source={0}; User Id=admin; Password={1};", "D:\product.MDB", "")
    Dim conn As OleDb.OleDbConnection
    Dim cmd As OleDb.OleDbCommand
    Dim sql As String

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'cmd = New OleDbCommand(sql, conn)
        'cmd.ExecuteNonQuery()
        conn = New OleDb.OleDbConnection(ConnStr)
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim dt As DataTable
        Dim tbl As DataTable
        Dim tbl2 As DataTable

        conn.Open()
        'tbl = conn.GetSchema() =数据库的所有架构信息。
        '获取用户表
        tbl = conn.GetSchema("tables", New String() {Nothing, Nothing, Nothing, "table"})
        'tbl = conn.GetSchema("tables") = 所有表，包括系统表。
        tbl2 = conn.GetSchema()
        '=不大支持的方法
        dt = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, New Object() {Nothing, Nothing, Nothing, "TABLE"})

        Me.ListBox1.Items.Clear()
        For i As Integer = 0 To dt.Rows.Count - 1
            Me.ListBox1.Items.Add(dt.Rows(i)("TABLE_NAME").ToString())
        Next

        Me.DataGridView1.DataSource = tbl
        Me.DataGridView2.DataSource = tbl2
        conn.Close()

    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Dim tbl As DataTable
        If String.IsNullOrEmpty(Me.TextBox1.Text) = False Then
            conn.Open()
            tbl = conn.GetSchema("columns", New String() {Nothing, Nothing, Me.TextBox1.Text})
            Dim rows() As DataRow = tbl.Select("", "Ordinal_Position")
            Me.ListBox2.Items.Clear()
            For Each row As DataRow In rows
                Me.ListBox2.Items.Add(row.Item("column_name"))
            Next
            Me.DataGridView2.DataSource = tbl
            conn.Close()
        End If

    End Sub

    Private Sub ListBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListBox1.SelectedIndexChanged
        If Me.ListBox1.SelectedItems.Count > 0 Then
            Me.TextBox1.Text = Me.ListBox1.SelectedItem.ToString
        End If
    End Sub

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnGetDatatable.Click
        Dim db As New AccessHelper
        db.connStr = ConnStr
        If Me.TextBox1.Text > "" Then
            db.Open()
            Me.DataGridView3.DataSource = db.GetDataView("select * from " & Me.TextBox1.Text)
        End If

    End Sub
End Class