使用 NSDate 创建事件答案

【问题标题】：Create Event with NSDate使用 NSDate 创建事件
【发布时间】：2011-02-18 10:10:49
【问题描述】：

有没有办法为 NSDate 创建事件？这是我的代码

    NSDate *date = [NSDate date];       
    NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
    [dateFormatter setDateFormat:@"MMMM d, yyyy"];
    NSString *dateStr = [dateFormatter stringFromDate:date]; 
    myDate.text = dateStr;

例如，如果日期 = 2 月 12 日； myDate .text = @"母亲节";

类似的东西

【问题讨论】：

标签： iphone sdk ios-4.2

【解决方案1】：

确实如此。您必须使用 NSDateComponents 将日期拆分为日和月

你可以这样写一个方法：

- (BOOL)date:(NSDate *)date isSameAsDay:(NSInteger)day andMonth:(NSInteger)month {
    NSUInteger dateFlags = NSDayCalendarUnit | NSMonthCalendarUnit;
    NSDateComponents *components = [[NSCalendar currentCalendar] components:dateFlags fromDate:date];
    if ([components day] == day && [components month] == month) {
        return YES;
    }
    return NO;
}

你会这样使用它

if ([self date:[NSDate date] isSameAsDay:12 andMonth:2]) {
   myDate.text = @"Mother Day";
}

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【解决方案2】：

应该这样做：

    NSDate *today = [NSDate date]; // Get ref to todays date
    NSCalendar *gregorian = [[NSCalendar alloc]
                             initWithCalendarIdentifier:NSGregorianCalendar];
    NSDateComponents *weekdayComponents =
    [gregorian components:(NSWeekdayOrdinalCalendarUnit | NSWeekdayCalendarUnit | NSMonthCalendarUnit) fromDate:today];
    NSInteger weekday = [weekdayComponents weekday]; // Sun == 1, Mon == 2, Tue...
    NSInteger weekdayOrdinal = [weekdayComponents weekdayOrdinal]; // First weekday month == 1 etc...
    NSInteger month = [weekdayComponents month];
    NSLog (@"%i %i %i", weekday, weekdayOrdinal, month);

    // Mothers day is every second Sunday of May so weekday == 1, weekdayOrdinal == 2, month == 5
    if ((weekday == 1) && (weekdayOrdinal == 2) && (month == 5)) {
        NSLog (@"It's mothers day!");
    }
    [gregorian release];

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