Objective-c 根据某一个时区的时间获取特定时区的时间

//获取默认时区的时间字符串

NSDateFormatter*formatter=[[NSDateFormatteralloc]init];

[formattersetDateFormat:@"yyyy-MM-ddHH:mm:ss"];

NSString*nowStr=[formatterstringFromDate:[NSDatedate]];

NSLog(@"nowtimewithoutsettingTimeZone\nDefaultTimeZone:%@,LocalTime%@",[formattertimeZone],nowStr);

NSDate*nowGMT=[formatterdateFromString:nowStr];

NSLog(@"当地时间->标准时间%@",nowGMT);

NSLog(@"标准时间->当地时间%@",[formatterstringFromDate:nowGMT]);

//获取特定时区的时间字符串

[formattersetTimeZone:[NSTimeZonetimeZoneWithName:@"America/Adak"]];

NSString*AmericanNow=[formatterstringFromDate:[NSDatedate]];

NSLog(@"nowtimewithcertaintimezone:%@LocalTime%@",[formattertimeZone],AmericanNow);

NSDate*AmericanGMT=[formatterdateFromString:AmericanNow];

NSLog(@"特定时区的时间->标准时间%@",AmericanGMT);

NSLog(@"标准时间->特定时区的时间%@",[formatterstringFromDate:AmericanGMT]);

[formatterrelease];

/*将系统默认时间转换称某个特别时区的时间[color=darkred][/color][size=x-large][/size]

Step1:获取系统默认时间的时间字符串

*/

NSDateFormatter*dateFormatter=[[NSDateFormatteralloc]init];

[dateFormattersetDateFormat:@"yyyy-MM-ddHH:mm:SS"];

NSString*defaultNowStr=[dateFormatterstringFromDate:[NSDatedate]];

NSLog(@"获取系统默认时间的时间字符串%@",defaultNowStr);

/*

Step2:获取标准时间

*/

NSDate*dateGMT=[dateFormatterdateFromString:defaultNowStr];

NSLog(@"获取标准时间%@",dateGMT);

/*将标准时间转换称特定时区的时间

*/

[dateFormattersetTimeZone:[NSTimeZonetimeZoneWithName:@"America/Adak"]];

NSString*localDateStr=[dateFormatterstringFromDate:dateGMT];

NSLog(@"将标准时间转换称特定时区的时间%@",localDateStr);

[dateFormatterrelease];

//将某个时区的特定时间转化称另一个时区的对应时间

/*

该例子将时区Asia/Tokyo的2011-12-3016：45：00转化为

时区America/Adak的相应时间

*/

NSDateFormatter*dateFormatter2=[[NSDateFormatteralloc]init];

[dateFormatter2setDateFormat:@"yyyy-MM-ddHH:mm:SS"];

NSString*fromTimeZone=[[NSStringalloc]initWithString:@"Asia/Tokyo"];

NSString*date_fromTimeZone=[[NSStringalloc]initWithString:@"2011-12-3016:45:00"];

[dateFormatter2setTimeZone:[NSTimeZonetimeZoneWithName:fromTimeZone]];

NSDate*dateOfGMT=[dateFormatter2dateFromString:date_fromTimeZone];

[fromTimeZonerelease];

[date_fromTimeZonerelease];

NSString*toTimeZone=[[NSStringalloc]initWithString:@"America/Adak"];

[dateFormatter2setTimeZone:[NSTimeZonetimeZoneWithName:toTimeZone]];

NSString*dateStrDst=[dateFormatter2stringFromDate:dateOfGMT];

NSLog(@"dateStrDst%@",dateStrDst);

[toTimeZonerelease];

[dateFormatter2release];