I'm new to iPhone development. I want to set default date to NSDate Object as string. I don't see any easy way or method...
I think there might be a method in NSCalender? If there's such a开发者_StackOverflow社区 method, please tell me.
Thanks in advance.
I'm not totally clear on what you are asking, but to create an instance of an NSDate object with the current date, one calls: NSDate * myDate = [NSDate date];
If you are saying that you have a c-string or NSString that needs to be parsed to initialize an NSDate object, that's another question.
I have some code posted here: How get a datetime column in SQLite with Objective C
that shows how to create NSDates from NSStrings using NSDateFormatter.
If you want to create an NSDate from a string, you need to use an NSDateFormatter to do it. It's important to note that the formatter will use the current locale's time zone when constructing the date, unless you put a time-zone in as part of the format. For more information about constructing time zones, see NSTimeZone.
For example, to create a date using the ubiquitous format '2011-01-16 00:00' in UTC, you would do:
NSDateFormatter* formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:@"yyyy-MM-dd HH:mm"];
// Only certain abbreviations are okay, like UTC. See docs for more info
[formatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"UTC"]];
NSDate* midnight_26_jan_2011_utc = [formatter dateFromString:@"2011-01-26 00:00"];
// this will display in your system locale
// (for me, it shows 2011-01-25 19:00 +0500 because I'm America/New_York time)
NSLog(@"date: %@", midnight_26_jan_2011_utc);
[formatter release];
Edit: Added time to format string.
You will need to look at the NSDate and NSDateFormatter classes. Here's a simple example of how to use them:
NSString* defaultDateString = [NSString stringWithFormat:@"2011-01-22 15:30:00"];
NSDateFormatter* dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
NSDate* defaultDate = [dateFormatter dateFromString:defaultDateString];
[dateFormatter release];
and if you wanted to get the string from a date you can just use:
NSString* defaultDateString = [dateFormatter stringFromDate:defaultDate];
NSDateFormatter *DateFormatter=[[NSDateFormatter alloc] init];
[DateFormatter setTimeZone:[NSTimeZone defaultTimeZone]];
[DateFormatter setDateFormat:@"yyyy-MM-dd hh:mm:ss"]; //here,you can set the date format as you need
NSDate *now = [[[NSDate alloc] init]autorelease];
NSString *theDate = [DateFormatter stringFromDate:now];
Now, you can use the string the date. :)
NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc]init]autorelease];
[dateFormatter setDateFormat:@"yyyy-mm-dd"];
NSDate *yourDate = [dateFormatter dateFromString:@"2011-01-26"];
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