PST和農業知識與科技時區錯誤

Question

當我運行下面的PST和AKST時區從不運行這段代碼......上述這些問題都完美運行：

NSTimeZone *pacificTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"PST"]; 
NSTimeZone *alaskaTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"AKST"]; 

但是這些沒有一個是運行：

}else if ([local isEqual: pacificTimeZone]) { 
    NSLog(@"Pacific"); 

} else if ([local isEqual: alaskaTimeZone]) { 
    NSLog(@"Alaska"); 

有什麼建議嗎？

NSTimeZone *local = [NSTimeZone localTimeZone]; 
    NSTimeZone *centralTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"CST"]; 
    NSTimeZone *easternTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"EST"]; 
    NSTimeZone *mountainTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"MST"]; 
    NSTimeZone *pacificTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"PST"]; 
    NSTimeZone *alaskaTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"AKST"]; 
    NSTimeZone *honoluluTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"HST"]; 

    NSLog(@"LOCAL TIME ZONE: %@", local); 

    NSLog(@"CST TIME %@", centralTimeZone); 
    NSLog(@"EST TIME %@", easternTimeZone); 
    NSLog(@"MST TIME %@", mountainTimeZone); 
    NSLog(@"PST TIME %@", pacificTimeZone); 
    NSLog(@"AKST TIME %@", alaskaTimeZone); 
    NSLog(@"HST TIME %@", honoluluTimeZone); 


    if ([local isEqual: centralTimeZone]) 
    { 
     NSLog(@"Central"); 

    } else if ([local isEqual: easternTimeZone]) { 
     NSLog(@"Eastern"); 

    } else if ([local isEqual: mountainTimeZone]) { 
     NSLog(@"Mountain"); 

    }else if ([local isEqual: pacificTimeZone]) { 
     NSLog(@"Pacific"); 

    } else if ([local isEqual: alaskaTimeZone]) { 
     NSLog(@"Alaska"); 

    } else if ([local isEqual: honoluluTimeZone]) { 
     NSLog(@"Honolulu"); 

    } 

謝謝！

Answer 1

從the documentation：

在一般情況下，你是從使用除了諸如「UTC」或「GMT」唯一實例縮寫氣餒。時區縮寫沒有標準，所以給定的縮寫，可以有多重含義 - 例如，「EST」是指東部時間同時在美國和澳大利亞

相反，使用timeZoneWithName。支持的時區來自IANA TZ database，您可以找到它們的列表here。

爲美國最常見的區域如下：

Alaska = "America/Anchorage" 
Hawaii = "Pacific/Honolulu" 
Pacific = "America/Los_Angeles" 
Arizona = "America/Phoenix" 
Mountain = "America/Denver" 
Central = "America/Chicago" 
Eastern = "America/New_York"