ASP.NET

Imports System.Data.OleDb

Partial Class _Default
    Inherits System.Web.UI.Page
    Dim cn As New OleDbConnection
    Dim cmd As New OleDbCommand
    Dim dr As OleDbDataReader

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        txtUsername.Focus()
        Label1.Text = ""
        Try
            With cn
                If .State = Data.ConnectionState.Open Then .Close()
                .ConnectionString = "Provider=microsoft.jet.oledb.4.0;data source=" & Server.MapPath("data\database.mdb")
                .Open()
            End With
        Catch ex As Exception
            MsgBox(ex.Message.ToString)
        End Try
    End Sub

Protected Sub btnLogin_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnLogin.Click
        If txtUsername.Text = "" Or txtPassword.Text = "" Then Exit Sub
        With cmd
            .CommandText = "Select * from tbluser Where userid = '" & Trim(txtUsername.Text) & "' and passid = '" Trim(txtPassword.Text) &"' "
            .Connection = cn
            dr = .ExecuteReader
        End With

        If dr.HasRows Then
            Session("name") = txtUsername.Text 'it will display o the other page, it depends 
            Response.Redirect("Main.aspx") 'my main.aspx is connected to my MASTER PAGE and all the other page
        Else
            Label1.Text = ("ERROR! " & txtUsername.Text)
        End If
    End Sub
End Class