iOS开发系列-NSDate

NSDate API

获取当前时间

获取时间戳

创建间隔指定时间戳的Date

// 获取昨天
NSTimeInterval time = 24 * 60 * 60;
NSDate *date = [NSDate dateWithTimeIntervalSinceNow: -time];
NSLog(@"%@", date);

// 明天
NSTimeInterval time = 24 * 60 * 60;
NSDate *tomorrowDate = [NSDate dateWithTimeIntervalSinceNow: time];
NSLog(@"%@", tomorrowDate);

比较两个时间

NSDate --> NSString

NSDate *nowDate = [NSDate date];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
dateFormatter.dateFormat = @"yyyy-MM-dd HH:mm:ss";

NSString *dateString = [dateFormatter stringFromDate:nowDate];
NSLog(@"%@", dateString);

NSString --> NSDate

NSString *timeStr = @"2018-09-10 15:24:51";

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
dateFormatter.dateFormat = @"yyyy-MM-dd HH:mm:ss";
NSDate *date = [dateFormatter dateFromString:timeStr];
NSLog(@"%@", date);

获取两个Date的间隔秒数