Sub btnLogin_Click(S As Object, E As EventArgs)
  Dim conLogin As OdbcConnection
  Dim cmdSelectLoginfo As OdbcCommand
  Dim dtrReaderLogin As OdbcDataReader
  Dim conStringLogin As String
  Dim SQLString As String
  Dim strUAID As String
  conStringLogin = System.Configuration.ConfigurationSettings.AppSettings.Get("ConnectionString")
  conLogin = New OdbcConnection( conStringLogin )
  SQLString = "SELECT UserID FROM Users WHERE UserName=? AND UserPassword=?"
  'MySQL:  SQLString = "SELECT UserID FROM Users WHERE UserName=@userName AND UserPassword=@userPass"
  cmdSelectLoginfo = New OdbcCommand( SQLString, conLogin )
  cmdSelectLoginfo.Parameters.Add("?userName", (txtUsername.Text.Trim()).ToString())
  'MySQL:  cmdSelectLoginfo.Parameters.Add("@userName",(txtUsername.Text.Trim()).ToString())
  cmdSelectLoginfo.Parameters.Add("?userPass", (txtPassword.Text.Trim()).ToString())
  'MySQL:  cmdSelectLoginfo.Parameters.Add("@userPass",(txtUsername.Text.Trim()).ToString())
  conLogin.Open()
  dtrReaderLogin = cmdSelectLoginfo.ExecuteReader()
  if dtrReaderLogin.hasrows then
    dtrReaderLogin.Close()
    strUAID = cmdSelectLoginfo.ExecuteScalar()
    Session("UAID") = strUAID
    conLogin.Close()
    Session("Login") = "Logged"
    Response.Redirect ("/loggedin.aspx")
  else
    Session("Login") = "Failed"
    Session("UAID") = ""
    conLogin.Close()
    dtrReaderLogin.Close()
    Response.Redirect ("/loggedin.aspx?log=fail")
    'or have this post back and enable a label field with lblname.Visible = true and lblname.Text = "login failed try again."
  end if
End Sub

Protected Sub btnSubmit_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSubmit.Click
        If Page.IsValid Then
            If DBFunction(txtUserName.Text.Trim(), txtPassword.Text.Trim()) Then
                Session("UserName") = txtUserName.Text
                FormsAuthentication.RedirectFromLoginPage(txtUserName.Text, False)
            Else

                lblMessage.Text = "Invalid Login!"
                lblMessage.ForeColor = Drawing.Color.Red

            End If

        End If
    End Sub


'Add thi function to connect to database.

  Function DBConnection(ByVal strUserName As String, ByVal strPassword As String) As Boolean
        Dim MyCmd As New SqlCommand("sp_ValidateUser", objConnection)
        MyCmd.CommandType = CommandType.StoredProcedure
        Dim objParam1, objParam2 As SqlParameter
        Dim objReturnParam As SqlParameter
        objParam1 = MyCmd.Parameters.Add("@UserName", SqlDbType.VarChar)
        objParam2 = MyCmd.Parameters.Add("@Password", SqlDbType.VarChar)
        objReturnParam = MyCmd.Parameters.Add("@Num_of_User", SqlDbType.Int)
        objParam1.Direction = ParameterDirection.Input
        objParam2.Direction = ParameterDirection.Input
        objReturnParam.Direction = ParameterDirection.ReturnValue
        objParam1.Value = txtUserName.Text
        objParam2.Value = txtPassword.Text
        Try
            If objConnection.State = ConnectionState.Closed Then
                objConnection.Open()
                MyCmd.ExecuteNonQuery()
            End If
            If objReturnParam.Value < 1 Then
                lblMessage.Text = "Invalid Login!"
                lblMessage.ForeColor = Drawing.Color.Red
            Else
                Return True
            End If
            objConnection.Close()
        Catch ex As Exception
            lblMessage2.Text = "Error Connecting to Database!" & ex.Message
            lblMessage2.ForeColor = Drawing.Color.Red
        End Try

    End Function




Add Stored Procedure  in you database QUERY ANALYZER:


CREATE  PROCEDURE sp_ValidateUser          	(
         		@UserName VARCHAR(50) = NULL,
         		@Password VARCHAR(50) = NULL,
         		@Num_of_User INT = 0
         	)
         AS
         	SET @Num_of_User = (SELECT COUNT(*) AS Num_of_User
         	FROM Members
         	WHERE UserName = @UserName AND Password = @Password)
         RETURN  @Num_of_User
         

 
label1.text="Hi " & Session[UserName] & "!"

Partial Class Login
    Inherits System.Web.UI.Page
    Dim objConnection As New SqlConnection("Data Source=SANDEEPTHAKUR\SANDY;database=Northwind;Integrated Security=SSPI")    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

End Sub