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Imports System.Data.OleDb
    Inherits System.Windows.Forms.Form
   Dim myconnection As New OleDbConnection("provider=microsoft.jet.oledb.4.0;data source=" & Application.StartupPath & "\student0.mdb") ‘------------------------- Á´½ÓÊý¾Ý¿â
    Dim mycommand As OleDbCommand
    Dim mydatareader As OleDbDataReader
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myconnection.Open()
        mycommand = New OleDbCommand("SELECT * from ¹ÜÀíÔ±±í where username='" & Trim(Txt_Username.Text) & "'and password='" & Trim(Txt_pwd.Text) & "'", myconnection)
        mydatareader = mycommand.ExecuteReader()