c# - Proper way to throw an error in a TPL Task so VS2012 does not complain -


i have founds threads similar not same forgive me if turns out duplicate. how 1 "throw" error inside task. have code , when conditions right throw error visual studio complains unhanded. afterwards performs should including _loaddatamappingfieldlisterror method. thought first continuewith suffice seems not. need create 2 separate tasks - 1 test , actual retrieval? seems little redundant. here code:

........ if (dcmapping.settingscomplete().isnullempty()) {     _taskcanceller = new cancellationtokensource();      _taskloader = task<object>.factory.startnew(() =>     {         //set indicator , first test connection make sure working         isloadingdatamappingfieldlist = true;          string test = dcmapping.testconnection();         if (test.isnotnullempty())             throw new dataconnectionexception(test);  // <--the throw in question         return dcmapping.getfieldnamelist();          // <--vs breaks here saying above unhandled     });      //if there error     _taskloader.continuewith(         antecendant => _loaddatamappingfieldlisterror(antecendant.exception),         _taskcanceller.token,         taskcontinuationoptions.onlyonfaulted,         taskscheduler.fromcurrentsynchronizationcontext());      //set receiving function     _taskloader.continuewith(         antecendant => _loaddatamappingfieldlistcomplete((list<string>)antecendant.result, remapfields),         _taskcanceller.token,         taskcontinuationoptions.notonfaulted,         taskscheduler.fromcurrentsynchronizationcontext()); } ........

you have option "just code" turned on. in case, indicating exception is unhandled respect "just code". exception caught framework code , stored in task.

i, personally, recommend turning off "just code" setting tends in way more helps.


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