Announcement Date and Effective Date when a company Dividend Declared?

General
1

in order to get dividends do i have to buy it before announcement date or effective date . what happen if i buy before announcement date and sell before effective date do still i get didvidend . plz tell me how to make sure i get dividend .

2

Please check this - http://zerodha.com/varsity/chapter/five-corporate-actions-and-its-impact-on-stock-prices/