Most efficient way to extract bit flags

Posted by Hallik on Stack Overflow See other posts from Stack Overflow or by Hallik
Published on 2010-05-07T21:50:16Z Indexed on 2010/05/07 21:58 UTC
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php

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bitmask

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bitmap

I have these possible bit flags.

1, 2, 4, 8, 16, 64, 128, 256, 512, 2048, 4096, 16384, 32768, 65536

So each number is like a true/false statement on the server side. So if the first 3 items, and only the first 3 items are marked "true" on the server side, the web service will return a 7. Or if all 14 items above are true, I would still get a single number back from the web service which is is the sum of all those numbers.

What is the best way to handle the number I get back to find out which items are marked as "true"?

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