where 条件不支持多于 1 个条件

Question

下面的代码我想使用多个条件但它不支持它只采用一个条件p.score<=35它只显示所有记录但是p.score<=50这个条件适用的记录是没有发现我该如何解决这个问题。

cs=(from e in db.Students
  join p in db.Marks
  on e.S_ID equals p.S_ID
  join t in db.Details
  on p.School_ID equals t.School_ID
  where  p.Score<=35 && p.Score <=50
  select new MyModel
  {
      S_Name = e.S_Name,
      Score = (int)p.Score,
      Status = p.Status,
      Address_City = t.Address_City,
      Email_ID = t.Email_ID,
      Accomplishments = t.Accomplishments
  }).ToList();

Answer 1

p.Score<=35 && p.Score <=50

与 p.Score<=35 相同。

我假设你真的想要

p.Score >= 35 && p.Score <= 50

即得分在 35 到 50 之间？

Answer 2

将 p.Score<=35 && p.Score <=50 更改为 (p.Score>=35 && p.Score <=50).

cs=(from e in db.Students
join p in db.Marks
on e.S_ID equals p.S_ID
join t in db.Details
on p.School_ID equals t.School_ID
where  (p.Score>=35 && p.Score <=50)
select new MyModel
{
  S_Name = e.S_Name,
  Score = (int)p.Score,
  Status = p.Status,
  Address_City = t.Address_City,
  Email_ID = t.Email_ID,
  Accomplishments = t.Accomplishments
}).ToList();

Answer 3

考虑一个标记列表 [15, 30, 35, 45, 50]

现在根据您在代码中应用的条件， where p.Score<=35 && p.Score <=50

你会得到[15,30,35]因为这些元素同时满足两个条件(<=35 && <=50)

你不会得到 [45,50] 因为它们只满足一个条件 (<=50)

由于您在两个条件之间应用了 && 子句，标记需要同时满足两个条件才能显示。只通过一个条件是不够的。

因此，您需要更改 where 子句。

如果要显示所有小于等于50的标记，需要写成where p.Score <=50
如果只显示小于或等于50但大于或等于35的标记，则需要写where p.Score>=35 && p.Score <=50

where 条件不支持多于 1 个条件

where condition not supporting more than 1 condition

c#

asp.net-mvc

entity-framework-6