Execute a script string

Hi!
how can I execute this code using vb .net windows forms and using the webbrowser control?
If the "popupScript" string has a javascript function how can I invoke the function?


Dim popupScript As String = "<script language='javascript'>" & _
"window.open('PopUp.aspx', 'CustomPopUp', " & _
"'width=200, height=200, menubar=yes, resizable=no')" & _
"</script>"

Page.RegisterStartupScript("PopupScript", popupScript)