iOS开发中NSDate时间戳的转换--
NSTimeInterval time =(NSTimeInterval )[model.day floatValue];
NSDate *date = [NSDate dateWithTimeIntervalSince1970:time];
//转化为字符串
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc]init];
[dateFormatter setDateFormat:@"yyyy/MM/dd hh:mm"];
NSString *dateStr = [dateFormatter stringFromDate:date];