Passing retrieving variables

I am using ASP .NET with VB script.
I have two aspx Files (webform1.aspx, webform2.aspx )
In webform1.aspx I use a text edit and a button.
In webform2.aspx I use a datagrid with a column which is a hyperlink.
When I click on the button of webform1.aspx the webform2.aspx
opens in a new window.
When I choose a row of datagrid I want to close webform2.aspx
window and the selected row value to displayed in the text edit of webform1.aspx form.

I want to ask how can I retrieve the selected row to the text edit of webform1.aspx.


Thanks