Forum Navigation
You need to log in to create posts and topics.
[OT]Different behavior for NSDictionary dictionaryWithObjectsAndKeys vs. literal container syntax
#1 · May 13, 2022, 10:08 pm
Posted by: fblistserve <fblistserve@...>
Was updating code and thought this behavior worth sharing ( apologies if it's been covered ). This is Objective-C but potentially applies to FB code.
This code creates a dictionary with one key because the only non-nil value is customer name ( with a key of kClientCustNameKey ) even though all values are possibly non-nil depending on data entered. All is good at runtime.
NSDictionary *returnedDict = [NSDictionary dictionaryWithObjectsAndKeys:
[dict objectForKey:kClientCustNameKey], ColClientNameClientCustSheet,
[dict objectForKey:kClientCustAddressKey], ColClientAddrClientCustSheet,
[dict objectForKey:kClientCustNoteKey], ColClientNoteClientCustSheet,
[dict objectForKey:kClientCustEmailKey], ColClientEmailClientCustSheet,
[dict objectForKey:kClientCustWebPageKey], ColClientWebClientCustSheet,
[dict objectForKey:kClientCustPhoneKey], ColClientPhoneClientCustSheet,
nil];
However, this code ( via the collection literal syntax ) generates a call to [NSDictionary dictionaryWithObjects:forKeys:count:]
which crashes ( in a later internal processing call ) because it finds a nil value.
NSDictionary *returnedDict = @{ ColClientNameClientCustSheet: dict[kClientCustNameKey],
ColClientAddrClientCustSheet: dict[kClientCustAddressKey],
ColClientNoteClientCustSheet: dict[kClientCustNoteKey],
ColClientEmailClientCustSheet: dict[kClientCustEmailKey],
ColClientWebClientCustSheet: dict[kClientCustWebPageKey],
ColClientPhoneClientCustSheet: dict[kClientCustPhoneKey]
};
--
To unsubscribe, send ANY message to: futurebasic-unsubscribe@welovegod.org To access the list archives, go to: http://welovegod.org/groups/futurebasic/