问题
I would like to define tasks using NSDictionary, which I'd like to save in a plist file (I didn't have much luck with Core Data so far), but got stuck at two points:
-- When using initWithObjectsAndKeys: I can change the data type to number or boolean, using NSDate's numberWithInt: and numberWithBool: methods, respectively. I can't seem to find the method to change the type to date though. I couldn't find anything like that in the documentation.
-- The second problem I ran into was with the nested arrays. How can I add them to the dictionary?
I have uploaded a picture to here of what I am trying to achieve. Thank you in advance!
回答1:
Do you mean NSNumber's +numberWithInt: and +numberWithBool: methods, not NSDate? It's NSNumber that defines those methods.
To convert a number to a date, it really depends on what the number is. If it's a UNIX timestamp, then [NSDate dateWithTimeIntervalSince1970:theTimestampInSeconds].
As for adding NSArray objects to a dictionary:
[yourDictionary setObject:yourArray forKey:@"SomeKey"];
You'll have to post some code if you need more help as your question isn't very clear.
回答2:
for the date you can also use numberWithInt: and the timeIntervalSince1970 method of NSDate to get a Timestamp. Theres also a Constructor for that Timestamp.
For nested Arrays you can simply add NSArray Objects in the Dictonary.
回答3:
Your plist should pick up the date format and store it using the Date type, so you can just ploug in the NSDate.
[plist setObject:theDate forKey:@"theDateKey"];
To save an array to your dictionary, use something like:
[NSDictionary dictionaryWithObjectsAndKeys:@"1", @"One", @"2", @"Two"];
来源：https://stackoverflow.com/questions/4582791/nesting-arrays-into-nsdictionary-object-objective-c