How to set the control value in another open aspx page
<p>My problem is simple, but I cannot find a way to solve it :( <br>
When the user clicks a specific button, I need to open a new aspx page (in a new window) so that he is able to select something that needs to be returned to the original page.
I was able to open the new page with window.open, however, I'm not able to set the selected value back in the original page. <br>
In summary, an input field needs to receive a string value from the opened page. I've tried with window.opener.getElementById(), but ASP.NET messes with the control's Id's, so I'm not able to determine the correct Id of the input field at runtime.<br>
Is there a simpler way to do this only with server side code (open the page and return the value), instead of using Javascript and window.opener (which is pretty bad, in my opinion)?<br>
If not, Any other simple solution is also welcome!<br><br></p>

<p>Thanks all!<br><br></p>

<p>Felipe</p>
