为NSDate添加天数

Question

我想要添加几天的日期,我有很多代码,但是没有一个代码在我看来下面显示的是我的代码,请有人帮我解决这个问题

int daysToAdd=[[appDlegateObj.selectedSkuData 
                                    objectForKey:@"Release Time"] intValue];

NSTimeInterval secondsForFollowOn=daysToAdd*24*60*60;

NSString *dateStr=[contentDic objectForKey:@"Date"];

NSDateFormatter *dateFormatter=[[NSDateFormatter alloc]init];

[dateFormatter setDateFormat:@"yyyy-MM-dd"];

NSDate *dateFromString=[[NSDate alloc]init];

dateFromString=[dateFormatter dateFromString:dateStr];

[dateFormatter release];

 NSDate *date=[dateFromString dateByAddingTimeInterval:secondsForFollowOn];

Answer 1

// Initialize stringified date presentation
NSString *myStringDate = @"2011-11-17";

// How much day to add
int addDaysCount = 30;

// Creating and configuring date formatter instance
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"yyyy-MM-dd"];

// Retrieve NSDate instance from stringified date presentation
NSDate *dateFromString = [dateFormatter dateFromString:myStringDate];

// Create and initialize date component instance
NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
[dateComponents setDay:addDaysCount];

// Retrieve date with increased days count
NSDate *newDate = [[NSCalendar currentCalendar] 
                              dateByAddingComponents:dateComponents 
                                              toDate:dateFromString options:0];

NSLog(@"Original date: %@", [dateFormatter stringFromDate:dateFromString]);
NSLog(@"New date: %@", [dateFormatter stringFromDate:newDate]);

// Clean up
[dateComponents release], dateComponents = nil;
[dateFormatter release], dateFormatter = nil;

输出:

Original date: 2011-11-17
New date: 2011-12-17

Answer 2

    NSDate *now = [NSDate date];
    int daysToAdd = 1;
    NSDate *newDate = [now dateByAddingTimeInterval:60*60*24*daysToAdd];