iOS 解析RFC3339时间格式
https://www.ietf.org/rfc/rfc3339.txt
https://zhuanlan.zhihu.com/p/31829454
-(NSString *)rfc3339DateFormatterStringToUTC8EndMicrosecond;{
// 2020-05-22T12:42:39.336702Z 格林尼治时间转本地时间 时间格式转换
NSString *result = [NSString stringWithFormat:@"%@Z",[self substringToIndex:self.length - 8]] ;
NSDateFormatter *rfc3339DateFormatter = [[NSDateFormatter alloc] init];
NSLocale *enUSPOSIXLocale = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"];
[rfc3339DateFormatter setLocale:enUSPOSIXLocale];
[rfc3339DateFormatter setDateFormat:@"yyyy'-'MM'-'dd'T'HH':'mm':'ss'Z'"];
[rfc3339DateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
// NSDate对象会自动根据当前时区加减时间 从而展示为当前时间
NSDate *createdAtZero = [rfc3339DateFormatter dateFromString:result];
NSDateFormatter *showDateFormatter = [[NSDateFormatter alloc] init];
// 2019/11/16 23:12:34
[showDateFormatter setDateFormat:@"yyyy/MM/dd HH:mm:ss"];
result = [showDateFormatter stringFromDate:createdAtZero];
return result;
}