iOS 計算某個時間到現在是多少月／天／時的代碼

傳入一個NSString類型的日期

格式如newsDate = @"2013-08-09 17:01";

或者newsDate = @"2013/08/09 17:01";

返回如果有一個月，就不返回天，依次類推。

-(NSString *)getUTCFormateDate:(NSString *)newsDate
{
//    newsDate = @"2013-08-09 17:01";
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm"];

    NSLog(@"newsDate = %@",newsDate);
    NSDate *newsDateFormatted = [dateFormatter dateFromString:newsDate];
    NSTimeZone *timeZone = [NSTimeZone timeZoneWithName:@"UTC"];
    [dateFormatter setTimeZone:timeZone];

    NSDate* current_date = [[NSDate alloc] init];

    NSTimeInterval time=[current_date timeIntervalSinceDate:newsDateFormatted];//間隔的秒數
    int month=((int)time)/(3600*24*30);
    int days=((int)time)/(3600*24);
    int hours=((int)time)%(3600*24)/3600;
    int minute=((int)time)%(3600*24)/60;
    NSLog(@"time=%d",(double)time);

    NSString *dateContent;

    if(month!=0){

        dateContent = [NSString stringWithFormat:@"%@%i%@",@"   ",month,@"個月前"];

    }else if(days!=0){

         dateContent = [NSString stringWithFormat:@"%@%i%@",@"   ",days,@"天前"];
    }else if(hours!=0){

         dateContent = [NSString stringWithFormat:@"%@%i%@",@"   ",hours,@"小時前"];
    }else {

        dateContent = [NSString stringWithFormat:@"%@%i%@",@"   ",minute,@"分鐘前"];
    }

//    NSString *dateContent=[[NSString alloc] initWithFormat:@"%i天%i小時",days,hours];


    [current_date release];
    [dateFormatter release];
    return dateContent;
}