检查日期是否在同一日历日

Question

是否有人可以帮助我弄清楚如何检查某日是否与今天同日。我想这需要在同一时区的同一天的0小时内创建一个日历日并检查，但到目前为止，我的尝试让我更加困惑于任何事情。

Answer 1

NSCalendar让你处理人天。所以，你可以实现一个类别是这样的：

@implementation NSDate (IsItToday) 
- (BOOL)isToday { 
    NSUInteger desiredComponents = NSEraCalendarUnit|NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit; 
    NSDateComponents *myCalendarDate = [[NSCalendar currentCalendar] components:desiredComponents fromDate:self]; 
    NSDateComponents *today = [[NSCalendar currentCalendar] components:desiredComponents fromDate:[NSDate date]]; 
    return [myCalendarDate isEqual:today]; 
} 
@end 

Answer 2

你应该好好读通过这个Dates and Times Programming Topics for Cocoa，但这样的事情应该工作：

NSDate *today = [NSDate date]; 
NSTimeInterval difference = [today timeIntervalSinceDate:otherDate]; 
NSTimeInterval secondsPerDay = 24 * 60 * 60; 
if (difference < secondsPerDay) 
{ 
    //same day as today 
}