Printing parameterised crystal reports direct to network printer

Hi Experts

I have a VB.net windows app written in VS 2005. I have a viewer page with a report on it, and it works great, users click on a datagrid print icon and the report pops up.

This is my code for that:

    Private Sub cvwPatients_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cvwPatients.Load

        Dim PR As New PatientReferraldb
        Dim dt As DataTable = PR.SelectForPrint(valReferrL_ID) 'send in report id

        rdPatients.SetDataSource(dt)

        With cvwPatients
            .ReportSource = rdPatients
            .ShowTextSearchButton = False
            .ShowExportButton = False
            .DisplayGroupTree = False
            .ShowGroupTreeButton = False
        End With
    End Sub

What I need to be able to do is go to my database to get a list of records not printed, and loop through and print them without a print dialog popping up.

Any ideas on how I might do this, I've googled PrintToPrinter, and guess this is what I must be using, but I cant find any examples of selecting a network printer, or how to pass parameters similar to the way I've done it to display the report.

Andy