How to know private key of a address from Bitcoin Wallet clients (Ex: Bitcoin core 0.10.0)
dumprivkey command on the debug console. You get to the debug console via the
help menu about dialog box I think. help menu > debug window > console tab.
and how to import a address into Bitcoin wallet ?
Which bitcoin wallet? if you mean core then importprivkey command in the debug console or command line should do it.
https://en.bitcoin.it/wiki/Original_Bitcoin_client/API_calls_listOh great ! I have the same question above but you have already answered it here. Sincere thanks !