Refeesh a DDL , when another page is closed.

Question

Consider Page1 and Page2.
PAge1 with RadioButtons,a DDL and a button B1.
The DDL has default text as "New" and others are populated from a DB.
Clicking B1 redirects to Page2.It has 2 scenarios.
- if "New" is selected in DDL and B1 clicked, Page2 opens in add mode.
- if other values are selected in DDL and B1 clicked, Page2 opens in edit. mode.

- If page2 opens in add mode , we can create some a thing and save in DB. These created are the once populated in page1 DDL.
MAIN SCENARIO::
When i create a new thing in Page2 and save in DB,the Page2 gets closed. After this i ned the Page2 DDL(only the DDL needs to be refreshed.) , to be refreshed.

How to DO?

Using javascript, hiddenfield and C# .