VB.net2008与ACCESS创建登录程序

　　我们知道VS2008已经为我们定制了相应的登录验证界面窗体了，这样我们就不需要再去创建一个窗体，而直接使用微软为我们做好的窗体界面吧。选择<项目>--<添加Windows窗体>--选择(登陆窗体)即可。如图4

　　创建完成后可看到漂亮的登录界面，默认窗体名称为：LoginForm1。我们需要双击窗体进入代码视图，进行声明。图5

　　在Public Class LoginForm1事件中输入相应代码：

Dim Conn As OleDb.OleDbConnection
Dim Cmd As OleDb.OleDbCommand
Dim Rd As OleDb.OleDbDataReader
Dim SQL As String
Dim Provider = "Provider=Microsoft.Jet.OLEDB.4.0"
Dim Database = "Data Source=C:Databasedata.mdb"

　　随后回到LoginForm1界面双击（确定）按钮进入代码视图，在 Private Sub OK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OK.Click中输入：

Private Sub OK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OK.Click
Conn = New OleDb.OleDbConnection(Provider & ";" & Database)
Conn.Open()
SQL = "Select * From 登录 Where Name='" & UsernameTextBox.Text & "' And Password='" & PasswordTextBox.Text & "'"
Cmd = New OleDb.OleDbCommand(SQL, Conn)
Rd = Cmd.ExecuteReader()
If Rd.Read() Then
Dim form1 As New Form1
form1.Show()
Me.Hide()
Else
MessageBox.Show("密码或用户名错误!", "错误提示!", MessageBoxButtons.OK, MessageBoxIcon.Error)
UsernameTextBox.Text = ""
PasswordTextBox.Text = ""
UsernameTextBox.Focus()
End If
Rd.Close()
Conn.Close()
End Sub