dynamic created dropdownlist and delete button

 I am creating a list of dynamically dropdownlist (within a table) in a placeholder. Beside each dropdownlist, there is a delete button. When delete button is clicked, it will delete the table (which will also delete the dropdownlist). However, here is what I encountered and I need some suggestions.
 
If there are 3 dropdownlists with delete buttons ID (btnDelete_0, btnDelete_1 and btnDelete_2) and I delete btnDelete_1 ? it will shows only btnDelete_0 and btnDelete_2 ? but when a postback occur, the second dropdownlist selected value is gone .. because it?s treated as btnDelete_1 ? how can I get this work around? If btnDelete_1 is deleted, btnDelete_2 should automatically treated as next dropdownlist (btnDelete_1) and kept it?s value?.
 
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