iOS 根据生日计算年龄和星座

1：根据生日计算年龄

```

NSString  * birthStr = @"1991-07-13";

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

formatter.dateFormat = @"yyyy-MM-dd";

NSDate  * birthDate =  [formatter dateFromString:birthStr];

NSTimeInterval dateDiff = [birthDate timeIntervalSinceNow];

计算年龄

int age1  =  trunc(dateDiff/(60*60*24))/365;

```

2：根据生日计算星座

```

-(NSString *)calculateConstellationWithMonth:(NSInteger)month day:(NSInteger)day

{

NSString *astroString = @"魔羯水瓶双鱼白羊金牛双子巨蟹狮子处女天秤天蝎射手魔羯";

NSString *astroFormat = @"102123444543";

NSString *result;

if (month<1 || month>12 || day<1 || day>31){

return @"错误日期格式!";

}

```

if(month==2 && day>29)

{

return @"错误日期格式!!";

}else if(month==4 || month==6 || month==9 || month==11) {

if (day>30) {

return @"错误日期格式!!!";

}

}

result=[NSString stringWithFormat:@"%@",[astroString substringWithRange:NSMakeRange(month*2-(day < [[astroFormat substringWithRange:NSMakeRange((month-1), 1)] intValue] - (-19))*2,2)]];

return [NSString stringWithFormat:@"%@座",result];

}