Having Trouble validating password

    Dim con As System.Data.SqlClient.SqlConnection
    Dim cmd As System.Data.SqlClient.SqlCommand
    Dim dr As System.Data.SqlClient.SqlDataReader
    Dim sqlStr As String
    Dim username As String
    Dim password As String
    Dim userid As Integer
    Dim testme As String

Private Sub LoginTest ()
       If usernamebox.Text.Length = 0 Then
            MsgBox("You must enter a username")
            usernamebox.Focus()
            Exit Sub
        ElseIf passwordbox.Text.Length = 0 Then
            MsgBox("You must enter a password")
            passwordbox.Focus()
            Exit Sub
        End If

        con = New SqlClient.SqlConnection(Module1.GetConnectionString())
        con.Open()
        sqlStr = "Select userid, username, password from users where username = '" & usernamebox.Text & "';"
        cmd = New SqlClient.SqlCommand(sqlStr, con)
        dr = cmd.ExecuteReader()
        If dr.HasRows Then
            dr.Read()
            userid = dr.Item("userid")
            username = dr.Item("username")
            password = dr.Item("password")
        Else
            MsgBox("Invalid Login Name")
            Exit Sub
        End If


        If passwordbox.Text = password Then
            MsgBox("Show roles Page")
        Else
            passwordbox.Text = ""
            ' The user name/password is invalid.
            MsgBox("Password invalid")
            passwordbox.Focus()
            Exit Sub
        End If

        MsgBox("Show roles Page")



        con.Close()
End Sub