consultation to have a modal popup page asp.net pass data to the parent page

asp.net vb
mysql
good morning
Experts I have a problem I have a ingresocotizaciones.aspx form where the user enters data provider and also I have a button that calls modal page popup where you select the supplier from grid that has the poup modal form (called consultaproveedor) I see the supplier charging the grid should be selecting the provider and upload it to ingresocotizaciones form with corresponding data (txtrut, txtproveedor etc)
select the rut supplier on the grid and send this page ingresocotizacion.aspx should close the modal modal load data into the ingresocotizacion.aspx
busquedaproveedor1.aspx (modal)
This is the code of the grid where I send variable data And as you would to send more data?
ingresocotizacion.axp receives data from the grid
<asp:GridView ID="GridView1" runat="server" AllowPaging="True" CellPadding="4" ...