ASP.NET

Hello;

I'm working on a simple login form in c# in asp.net. I'd like to bind a key to the password and then save it in encrypted form. When the user logs in, he should enter his key and password. The key will be bind to the password and then compared to the one stored on the database.

Please help me with the binding process and encryption.
Thanks.

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load

    If Not IsPostBack Then
        ddlParks.AppendDataBoundItems = True
        Dim strQuery As [String] = "Select parkID, parkName from ParksCategory"
        Dim con As New SqlConnection(strConnString)
        Dim cmd As New SqlCommand()
        cmd.CommandType = CommandType.Text
        cmd.CommandText = strQuery
        cmd.Connection = con
        Try
            con.Open()
            ddlParks.DataSource = cmd.ExecuteReader()
            ddlParks.DataTextField = "parkName"
            ddlParks.DataValueField = "parkID"
            ddlParks.DataBind()
        Catch ex As Exception
            Throw ex
        Finally
            con.Close()
            con.Dispose()
        End Try
    End If
End Sub
Protected Sub ddlParks_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs) Handles ddlParks.SelectedIndexChanged

    Dim strQuery As [String] = "select subcatID, subcatName from SubCategory" _
                                & "where parkID=@parkID AND Status=1"
    Dim con As New SqlConnection(strConnString)
    Dim cmd As New SqlCommand()
    cmd.Parameters.AddWithValue("@parkID", _
                         ddlParks.SelectedItem.Value)
    cmd.CommandType = CommandType.Text
    cmd.CommandText = strQuery
    cmd.Connection = con
    Try
        con.Open()

        dr = cmd.ExecuteReader()

        Do While dr.HasRows
            lblfacility.Text = dr.GetName(1)

            Do While dr.Read()

                  lblfacility.Text = dr.GetString(1)
            Loop

            dr.NextResult()
        Loop

    Catch ex As Exception
        Throw ex
    Finally
        con.Close()
        con.Dispose()
    End Try
End Sub