iphone - Putting isCancelled Property in an NSOperationQueue -

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• how cancel out of operation created addoperationwithblock? 2 answers

so, using addoperationwithblock^{}method of nsoperationqueue , want put fine grained iscancelled property check @ points in operation code. how instance of operation run while in block?

for example, code snippet:

[operationqueueinstance addoperationwithblock:^{     if (!???.iscancelled){         nslog(@"instruction 1");     }     if (!???.iscancelled){         nslog(@"instruction 2");     }      nslog(@"instruction 3");  }]; 

how instance of operation block run in can evaluate iscancelled property instructions?

tia

from apple docs:

you should not attempt reference newly created operation object or divine type information.

you instantiate nsblockoperation , assign variable keep explicit reference instead.

addoperationwithblock seems shortcut whenever don't need reference operation object.

make sure mark block operation __block storage qualifier avoid retain cycles.