iOS开发NSDate、NSString、时间戳之间的转化

//将UTCDate(世界标准时间)转化为当地时区的标准Date（钟表显示的时间）

//NSDate *date = [NSDate date]; 2018-03-27 06:54:41 +0000 

//转化后：2018-03-27 14:54:41 +0000 

-(NSDate *)getLocalDateFromUTCDate:(NSDate *)UTCDate{

NSTimeZone *tz = [NSTimeZone defaultTimeZone]; 7NSInteger seconds = [tz secondsFromGMTForDate: UTCDate]; 

 return [NSDate dateWithTimeInterval: seconds sinceDate: UTCDate]; 

} 

---

//将当地时区的标准Date转化为UTCDate 

//当前当地的标准时间：2018-03-27 14:54:41 +0000 

//转化为世界标准时间:2018-03-27 06:54:41 +0000

 -(NSDate *)getUTCDateFromLocalDate:(NSDate *)LocalDate{ 

NSTimeZone *tz = [NSTimeZone defaultTimeZone]; 

NSInteger seconds = -[tz secondsFromGMTForDate: LocalDate];

 return [NSDate dateWithTimeInterval: seconds sinceDate: LocalDate]; 

} 

---

//根据UTCDate获取当前时间字符串（钟表上显示的时间） 

//输入：[NSDate date] 2018-03-27 07:44:05 +0000 

//输出：2018-03-27 15:44:05 

 -(NSString *)localStringFromUTCDate:(NSDate *)UTCDate{ 

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc]init]; 

NSTimeZone *tz = [NSTimeZone defaultTimeZone]; 

 [dateFormatter setTimeZone:tz]; 

[dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"]; 

NSString* result=[dateFormatter stringFromDate:UTCDate]; 

return result; 

} 

---

//根据UTC字符串获取当前时间字符串（钟表上显示的时间） 

//输入：2018-03-27 07:44:05 

//输出：2018-03-27 15:44:05 

-(NSString *)localStringFromUTCString:(NSString *)UTCString{ 

//先将UTC字符串转为UTCDate; 

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];

NSTimeZone *tz = [NSTimeZone timeZoneWithAbbreviation:@"GMT"];

 [dateFormatter setTimeZone:tz]; 

[dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];

NSDate *UTCDate = [dateFormatter dateFromString:UTCString]; 

 [dateFormatter setTimeZone:[NSTimeZone defaultTimeZone]];

NSString* result = [dateFormatter stringFromDate:UTCDate]; 

 return result; 

 } 

---

//将当前时间字符串转为UTCDate 

-(NSDate *)UTCDateFromLocalString:(NSString *)localString{ 

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; 

[dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];

NSDate *date = [dateFormatter dateFromString:localString]; 

return date;

}

---

//将当前时间字符串转为UTC字符串 

 -(NSString *)UTCStringFromLocalString:(NSString *)localString{

NSDate *date = [self UTCDateFromLocalString:localString]; 

NSString *string= [NSString stringWithFormat:@"%@",date]; 

NSString *result = [stringsubstringToIndex:string.length-6];

 return result; 

 } 

---

//UTCDate转UTC字符串

-(NSString *)UTCStringFromUTCDate:(NSDate *)UTCDate{ 

NSDateFormatter *dataFormatter = [[NSDateFormatter alloc]init]; 

[dataFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];

NSTimeZone *tz = [NSTimeZone timeZoneWithAbbreviation:@"GMT"];

 [dataFormatter setTimeZone:tz];

NSString *UTCString = [dataFormatter stringFromDate:UTCDate]; 

return UTCString; 

} 

---

//将当前时间（UTCDate）转为时间戳 

-(NSString *)timeStampFromUTCDate:(NSDate *)UTCDate{ 

NSTimeInterval timeInterval = [UTCDate timeIntervalSince1970]; 

// *1000,是精确到毫秒；这里是精确到秒;

 NSString *result = [NSString stringWithFormat:@"%.0f",timeInterval];

return result; 

} 

---

//当前时间字符串(钟表上显示的时间)转为时间戳 

-(NSString *)timeStamapFromLocalString:(NSString *)localString{

//先转为UTCDate 

NSDate *UTCDate = [self UTCDateFromLocalString:localString];

NSString *timeStamap = [self timeStampFromUTCDate:UTCDate];

return timeStamap;

}

---

//将UTCString转为时间戳

-(NSString *)timeStamapFromUTCString:(NSString *)UTCString{

//先将UTC字符串转为UTCDate;

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];

NSTimeZone *tz = [NSTimeZone timeZoneWithAbbreviation:@"GMT"];

 [dateFormatter setTimeZone:tz];

[dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];

NSDate *UTCDate = [dateFormatter dateFromString:UTCString];

NSString *timeStamap = [self timeStampFromUTCDate:UTCDate];

return timeStamap;

}

---

//时间戳转UTCDate

-(NSDate *)UTCDateFromTimeStamap:(NSString *)timeStamap{

NSTimeInterval timeInterval=[timeStamap doubleValue];

//   1000; 传入的时间戳timeStamap如果是精确到毫秒的记得要/1000

NSDate *UTCDate=[NSDate dateWithTimeIntervalSince1970:timeInterval];

return UTCDate;

}