高级查询

  模糊查(包含):.Contains(name)
  开头:.StartsWith(name)
  结尾:.EndsWith(name)

  个数:.Count()
  最大值:Max(r => r.price);
  最小值:Min(r => r.price);
  平均值:Average(r => r.price);
  求和:Sum(r => r.price);

  升序:OrderBy(r => r.price)
  降序:OrderByDescending(r => r.price)

  分页:
  public List<car> Select(int count, int number)
  {
    return con.car.Skip(count * (number - 1)).Take(count).ToList();
  }

  组合查询:
  集合的交集
  All.Intersect(oillist)