iOS GMT 时间的转换（Mon Nov 05 2018 03

由于我们后端给返回的时间格式是GMT 格式，需要我们前端对格式进行转换，我查了好多资料iOS都没有相关的方法，最后自己写的。然后自己对MGT UTC 时间格式转换做了下总结，希望能对以后遇到问题的同行有所帮助。

1. MGT 时间 转本地时间格式

我们后端返回的GMT 格式

Mon Nov 05 2018 03:37:51 GMT+0000 (Coordinated Universal Time)

----> 2018/11/5 11:37:51

附上代码

+(NSString *)convertGMTtoLocalTimeConversion:(NSString *)gmtDateStr
{
NSDateFormatter * formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:@"EEE MMM dd yyyy HH:mm:ss 'GMT'Z' (Coordinated Universal Time)'"];

NSTimeZone * local = [NSTimeZone systemTimeZone];
[formatter setTimeZone:local];
[formatter setLocale:[[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"]];
NSDate * localDate = [formatter dateFromString:gmtDateStr]; 
NSTimeInterval localTimeInterval = [localDate timeIntervalSinceReferenceDate];
NSDate * localCurrentDate = [NSDate dateWithTimeIntervalSinceReferenceDate:localTimeInterval];
[formatter setDateFormat:@"yyyy/MM/dd HH:mm:ss"];
NSString *dateString = [formatter stringFromDate:localCurrentDate];
 
// NSLog(@"时间-localCurrentDate----dateString--：%@ %@",localCurrentDate,dateString);

return dateString;

}

2.iOS生成GMT时间 方法
/**
2018-11-09 09:38:39 -> Sun, 09 Nov 2018 01:38:39 GMT
*/
NSDate *date = [NSDate date];
NSTimeZone *tzGMT = [NSTimeZone timeZoneWithName:@"GMT"];
[NSTimeZone setDefaultTimeZone:tzGMT];
NSDateFormatter *iosDateFormater=[[NSDateFormatter alloc]init];
iosDateFormater.dateFormat=@"EEE, d MMM yyyy HH:mm:ss 'GMT'";
iosDateFormater.locale=[[NSLocale alloc]initWithLocaleIdentifier:@"en_US"];
NSString *dateStr = [iosDateFormater stringFromDate:date];

输出结果为 Sun, 09 Nov 2018 01:38:39 GMT

3. UTC 时间转本地时间
   /**
   2018-11-09 09:38:39 -> 2018/11/09 09:38:39
   */

• (NSString *)getLocalDateFormateUTCDate:(NSString *)utcStr { NSDateFormatter *format = [[NSDateFormatter alloc] init];
  format.dateFormat = @"yyyy/MM/dd HH:mm:ss";
  format.timeZone = [NSTimeZone timeZoneWithName:@"UTC"];
  NSDate *utcDate = [format dateFromString:utcStr];
  format.timeZone = [NSTimeZone localTimeZone];
  NSString *dateString = [format stringFromDate:utcDate];
  return dateString;
  }