将[NSDate日期]转换为本地化的UTC日期字符串

时间:2016-12-14 05:59:56

标签: ios objective-c timezone nsdate

我有一个NSDate对象,我发送给我们使用的API。我们的应用程序在全球范围内使用,因此API希望日期为UTC,例如:

"/Date(1481704200000)/"

但是,日期需要考虑时区偏移,因为API /服务器没有为我们这样做。如果我们不这样做,当我们在服务器上查看它时,日期是不正确的。

我正在执行以下操作,这似乎产生了错误的日期:

// Offset
float timezoneoffset = [[NSTimeZone localTimeZone] secondsFromGMT];

// Date
CFTimeInterval startDate = [[NSDate date] timeIntervalSince1970];
startDate = startDate - timezoneoffset;
NSString *dateStarted = [NSString stringWithFormat:@"/Date(%.0f000)/", startDate];

如何正确考虑本地时区并创建格式正确的UTC日期字符串?

3 个答案:

答案 0 :(得分:5)

无需任何时区操作。

private Toolbar toolbar;
toolbar = (Toolbar) findViewById(R.id.activity_menubar_toolbar);
setSupportActionBar(toolbar);
autoCompleteTextView = (AutoCompleteTextView)toolbar.findViewById(R.id.autoCompleteTextView);

无论用户的时区如何,都以UTC为单位提供时间。

试试吧。在测试设备上使用几个不同的时区设置运行此代码,您将在每种情况下获得相同的结果。

答案 1 :(得分:1)

double secsUtc1970 = [[NSDate date]timeIntervalSince1970];

现在是UTC,(至少在使用下面的方法之后) 要将此时间存储为UTC(自参考日期1970起),请使用

NSTimeZone *timeZone = [NSTimeZone defaultTimeZone];
// or Timezone with specific name like
// [NSTimeZone timeZoneWithName:@"Europe/Riga"] 
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setTimeZone:timeZone];
[dateFormatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"];
NSString *localDateString = [dateFormatter stringFromDate:currentDate];

设置日期格式化程序以输出本地时间:

NSDate

NSTimeZone* timeZone = [NSTimeZone timeZoneWithAbbreviation:@"GMT"]; NSString* timeZoneName = [timeZone localizedName:NSTimeZoneNameStyleStandard locale:[NSLocale currentLocale]]; NSLog(@"Name : %@", timeZoneName); 对象始终使用UTC作为时间参考,但日期的字符串表示不一定基于UTC时区。

要获得时区,您可以使用:

[NSTimeZone abbreviationDictionary]

如果您致电NSLog(@"%@",[NSTimeZone abbreviationDictionary]); ,我们会收到包含所有可用缩写词的词典。

2015-07-10 11:44:05.954 APP[1472:26120] {
    ADT = "America/Halifax";
    AKDT = "America/Juneau";
    AKST = "America/Juneau";
    ART = "America/Argentina/Buenos_Aires";
    AST = "America/Halifax";
    BDT = "Asia/Dhaka";
    BRST = "America/Sao_Paulo";
    BRT = "America/Sao_Paulo";
    BST = "Europe/London";
    CAT = "Africa/Harare";
    CDT = "America/Chicago";
    CEST = "Europe/Paris";
    CET = "Europe/Paris";
    CLST = "America/Santiago";
    CLT = "America/Santiago";
    COT = "America/Bogota";
    CST = "America/Chicago";
    EAT = "Africa/Addis_Ababa";
    EDT = "America/New_York";
    EEST = "Europe/Istanbul";
    EET = "Europe/Istanbul";
    EST = "America/New_York";
    GMT = GMT;
    GST = "Asia/Dubai";
    HKT = "Asia/Hong_Kong";
    HST = "Pacific/Honolulu";
    ICT = "Asia/Bangkok";
    IRST = "Asia/Tehran";
    IST = "Asia/Calcutta";
    JST = "Asia/Tokyo";
    KST = "Asia/Seoul";
    MDT = "America/Denver";
    MSD = "Europe/Moscow";
    MSK = "Europe/Moscow";
    MST = "America/Denver";
    NZDT = "Pacific/Auckland";
    NZST = "Pacific/Auckland";
    PDT = "America/Los_Angeles";
    PET = "America/Lima";
    PHT = "Asia/Manila";
    PKT = "Asia/Karachi";
    PST = "America/Los_Angeles";
    SGT = "Asia/Singapore";
    UTC = UTC;
    WAT = "Africa/Lagos";
    WEST = "Europe/Lisbon";
    WET = "Europe/Lisbon";
    WIT = "Asia/Jakarta";
}

结果:

{{1}}

希望这会有所帮助。

答案 2 :(得分:-1)

public let Date_format_Default:String = "yyyy-MM-dd HH:mm:ss"

为UTC字符串设置此格式字符串;

public let Date_format_Z:String = "yyyy-MM-dd HH:mm:ssZ"
public let Time_zone_UTC:String = "UTC"

open class func convertDate2UTC(_ date:String)->(String){
    var df_:DateFormatter?=DateFormatter()
    df_!.dateFormat=Date_format_Z
    let tz_=TimeZone(identifier: Time_zone_UTC)
    df_!.timeZone=tz_
    let df_s=df_!.date(from: date)

    df_!.dateFormat=Date_format_Default
    let string_=df_!.string(from: df_s!)

    df_ = nil
    return string_;
}