Imports System.Data.OleDb
'注意:以上一句必须写,不然就不能用OleDb类。
Public Class Form1
    Inherits System.Windows.Forms.Form
    '第一步,定义赋值连接数据库的连接字符串
    Dim ConnStr As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source= stu_data.mdb"
    '第二步,定义和建立连接数据库的连接字符串
    Dim conn As OleDbConnection = New OleDbConnection(ConnStr)
    '第三步,定义数据库适配器,用来管理数据库中的表
    Dim adapter As OleDbDataAdapter = New OleDbDataAdapter
    '第四步,定义和建立数据集
    Dim ds As DataSet = New DataSet
    '注:以上第一、二步可以合成一步。第四步也可以在具体子程序中定义,甚至多个。
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        '准备查询语句
        Dim QueryStr As String = "SELECT * FROM students"
        '在adapter管理下,执行conn连结下的查询语句
        adapter.SelectCommand = New OleDbCommand(QueryStr, conn)
        '将执行结果填充到数据集ds中
        adapter.Fill(ds, "students")
        '把数据集邦定到Datagrid1表格控件上
        DataGrid1.DataSource = ds.Tables(0)
        '下面的两个表与前面第一个表的操作类似。
        Dim QueryStr1 As String = "SELECT * FROM student_info"
        adapter.SelectCommand = New OleDbCommand(QueryStr1, conn)
        adapter.Fill(ds, "student_info")
        DataGrid2.DataSource = ds.Tables(1)
        Dim QueryStr2 As String = "SELECT * FROM prac_desi"
        adapter.SelectCommand = New OleDbCommand(QueryStr2, conn)
        adapter.Fill(ds, "prac_desi")
        DataGrid3.DataSource = ds.Tables(2)