How to get popup data into textbox in parent page

Question

Hello Friends............

I have one radio button .....if i will click on radio button then one grid view  popup will open.....

in grid view pop up i will select one grid then data will come to parent page on text box.....

Please i want both parent and child .aspx and .cs page code............

For Example:

 

 Parent.aspx

code	3434
seqno	5454

O----Exisiting Branch(Radio Button)Here i will click

code-- 

POpUp.aspx Page 

Select	code	seqno	description
Select	3434	5454	dfvdf

one Popup Grid Data window will come