Objective-C 如何获取毫秒级的NSDate？ dateFromString：方法忽略毫秒

Question

我使用了以下代码：

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
dateFormatter.timeZone = [NSTimeZone localTimeZone];
dateFormatter.locale = [NSLocale localeWithLocaleIdentifier:@"en_US_POSIX"];
dateFormatter.dateFormat = @"yyyy-MM-dd'T'HH:mm:ss.SSS'Z'";
NSString *str = [dateFormatter stringFromDate:[NSDate date]];
dateFormatter.dateFormat = @"yyyy-MM-dd'T'HH:mm:ss.SSS'Z'";
NSDate *dateToday =  [dateFormatter dateFromString:str];

此处 str 的值对于 .milliseconds 是正确的，但是当我尝试在 NSDate 中使用相同的 datFormatter 转换同一个字符串时，它 returns NSdate 没有毫秒。

Answer 1

使用这些函数并尝试记录日期以获得准确的结果:-

-(NSString *)stringFromDate:(NSDate *)date{
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    dateFormatter.timeZone = [NSTimeZone localTimeZone];
    dateFormatter.locale = [NSLocale localeWithLocaleIdentifier:@"en_US_POSIX"];
    dateFormatter.dateFormat = @"yyyy-MM-dd'T'HH:mm:ss.SSS'Z'";
    NSString *str = [dateFormatter stringFromDate:[NSDate date]];
    NSLog(@"Date : %@",str);
    return str;
}

-(NSDate *)dateFromString:(NSString *)dateString{
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    dateFormatter.timeZone = [NSTimeZone localTimeZone];
    dateFormatter.locale = [NSLocale localeWithLocaleIdentifier:@"en_US_POSIX"];
    dateFormatter.dateFormat = @"yyyy-MM-dd'T'HH:mm:ss.SSS'Z'";
    NSDate *date=[dateFormatter dateFromString:dateString];
    NSLog(@"Date : %@",[dateFormatter stringFromDate:date]);
    return date;
}

Objective-C 如何获取毫秒级的NSDate？ dateFromString：方法忽略毫秒

In Objective-C how to get NSDate with milliseconds? dateFromString: method is ignoring milliseconds

date

objective-c

nsdate

nsdateformatter