Many thanks for all the suggestions, much appreciated. Although -timeIntervalSinceReferenceDate: may indeed be a workable solution as the XML is our own format so I could make this choice, for now I think I'd like to retain a human-readable date. Mike's suggestion of creating one NSDateFormatter and passing all of the dates through that (as opposed to relying on the standard methods which most likely create a formatter per-instance) boosted performance significantly, so I'm going to see if I can squeeze more speed elsewhere and go with that.
Thanks again! All the best, Keith --- On Mon, 1/25/10, Mike Abdullah <cocoa...@mikeabdullah.net> wrote: > From: Mike Abdullah <cocoa...@mikeabdullah.net> > Subject: Re: Fastest way to convert an NSDate into an NSString > To: "Keith Blount" <keithblo...@yahoo.com> > Cc: cocoa-dev@lists.apple.com > Date: Monday, January 25, 2010, 8:33 PM > This approach is probably creating a > new NSDateFormatter for each date processed. What if you > create your own formatter and use that for all dates? > > On 25 Jan 2010, at 20:23, Keith Blount wrote: > > > Hello, > > > > I am in the process of converting the data format for > my application from one that just uses the NSKeyedArchiver > methods to archive my objects to a file on disk to using the > NSXML classes to generate a custom XML file (I need to do > this for compatibility purposes). My main data object is > essentially a (potentially very long) list (or rather tree) > of items, each of which have two or three dates associated > with them (among other things). > > > > Having completed the initial conversion process, it > turns out that currently my XML-writing methods (using > NSXMLElement, NSXMLDocument etc) are much, much slower than > using NSKeyedArchiver. Using Sample, it turns out that a lot > of the time is spent converting the NSDates for each of the > items in my list to string objects. I have tried this using > two different methods: > > > > NSDate *someDate = ... > > > > [xmlElement addAttribute:[NSXMLNode > attributeWithName:"SomeDate" stringValue:[someDate > descriptionWithLocale:nil]]]; > > > > and > > > > NSXMLNode *attribute = [[NSXMLNode alloc] > initWithKind:NSXMLAttributeKind]; > > [attribute setName:@"SomeDate"]; > > [attribute setObjectValue:someDate] > > [xmlElement addAttribute:attribute]; > > [attribute release]; > > > > But either way suffers the same performance hit. So, > my question is, does anyone know of a much faster and more > efficient way of converting NSDates to NSStrings? (A > possible solution would be to change my data model to store > these dates as strings internally so that the conversion is > already done when they come to be written to file, but I was > hoping for a more elegant solution.) > > > > Many thanks and all the best, > > Keith > > > > > > > > _______________________________________________ > > > > Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) > > > > Please do not post admin requests or moderator > comments to the list. > > Contact the moderators at > cocoa-dev-admins(at)lists.apple.com > > > > Help/Unsubscribe/Update your Subscription: > > http://lists.apple.com/mailman/options/cocoa-dev/cocoadev%40mikeabdullah.net > > > > This email sent to cocoa...@mikeabdullah.net > > _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
