ios - NSString 到 NSDate 的转换 - 不正确的结果

Question

简而言之，我计划获取当前日期时间，更改时间并通过将+0800应用于时区使其成为马来西亚本地时间。

结果出乎意料:

-(NSDate *)departureDateTime
{
    NSDate *date = [NSDate date];
    NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier: NSGregorianCalendar];
    NSDateComponents *components = [gregorian components: NSUIntegerMax fromDate: date];
    [components setHour: 7];
    [components setMinute: 59];
    [components setSecond: 17];

    NSDate *newDate = [gregorian dateFromComponents: components];

    NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
    [dateFormat setDateFormat:@"yyyy-mm-dd HH:mm:ss Z"];
    [dateFormat setLocale:[NSLocale currentLocale]];


    NSString *newDateString = [NSString stringWithFormat:@"%@",newDate];
    NSString *maskString = [NSString stringWithFormat:@"%@", [newDateString substringToIndex:20]];
    NSString *append = [maskString stringByAppendingString:@"+0800"];
    NSLog(@"%@",append);


    NSDate *finalLocalDate = [dateFormat dateFromString:append];

    return finalLocalDate;
}

结果:

对于 NSLog 附加:2013-12-07 23:59:17 +0800

但最终本地日期:2013-01-07 15:59:17 +0000

Answer 1

通过更短的解决方案找到了答案，所以我发布在这里以防将来对任何人有帮助。

对于返回，问题是不同的时区，所以通过添加这一行

[components setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:(+0*3600) ] ];

我们将时区设置为系统时区，然后删除不必要的代码:

-(NSDate *)departureDateTime
{
    NSDate *date = [NSDate date];
    NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier: NSGregorianCalendar];
    NSDateComponents *components = [gregorian components: NSUIntegerMax fromDate: date];

    [components setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:(+0*3600) ] ];
    [components setHour: 7];
    [components setMinute: 59];
    [components setSecond: 17];

    NSDate *newDate = [gregorian dateFromComponents: components];
    NSLog(@"%@",newDate);

    return newDate;
}

正确结果:2013-12-08 07:59:17 +0000