SQL 在 where 子句中使用 Array 进行 Linq 查询？
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Linq query with Array in where clause?
提问by Matt Dell
I have searched for this, but still can't seem to get this to work for me. I have an array of Id's associated with a user (their Organization Id). These are placed in an int[] as follows:
我已经搜索过这个，但似乎仍然无法让它对我来说有效。我有一组与用户相关联的 ID（他们的组织 ID）。它们被放置在一个 int[] 中，如下所示：
int[] OrgIds = (from oh in this.Database.OrganizationsHierarchies
join o in this.Database.Organizations on oh.OrganizationsId equals o.Id
where (oh.Hierarchy.Contains(@OrgId))
|| (oh.OrganizationsId == Id)
select o.Id).ToArray();
The code there isn't very important, but it shows that I am getting an integer array from a Linq query.
那里的代码不是很重要，但它表明我从 Linq 查询中获取了一个整数数组。
From this, though, I want to run another Linq query that gets a list of Personnel, that code is as follows:
尽管如此，我想运行另一个获取人员列表的 Linq 查询，代码如下：
List<Personnel> query = (from p in this.Database.Personnels
where (search the array)
select p).ToList();
I want to add in the where clause a way to select only the users with the OrganizationId's in the array. So, in SQL where I would do something like "where OrganizationId = '12' or OrganizationId = '13' or OrganizatonId = '17'."
我想在 where 子句中添加一种仅选择数组中具有 OrganizationId 的用户的方法。因此，在 SQL 中，我会执行诸如“where OrganizationId = '12' 或 OrganizationId = '13' 或 OrganizatonId = '17'”之类的操作。
Can I do this fairly easily in Linq / .NET?
我可以在 Linq / .NET 中轻松地做到这一点吗？
回答by Adam Robinson
While this is probably better suited to a join, you can use this:
虽然这可能更适合连接，但您可以使用它：
List<Personnel> query =
(from p in this.Database.Personnels
where OrgIds.Contains(p.OrgID) select p).ToList();
This will translate into SQL something like..
这将转换为 SQL 之类的东西。
where OrgID in (1,2,...,n)
回答by Noldorin
A check using the Containsmethod should do the job here.
使用该Contains方法的检查应该在这里完成工作。
var query = (from p in this.Database.Personnels
where OrgIds.Contains(p.OrganisationId)
select p).ToList();
回答by Matt Dell
I wanted to give Adam credit for the answer, but I also wanted to share the code I used to make this work:
我想感谢 Adam 的回答，但我也想分享我用来完成这项工作的代码：
List<int> OrgIds= (from oh in this.Database.OrganizationsHierarchies
join o in this.Database.Organizations on oh.OrganizationsId equals o.Id
where (oh.Hierarchy.Contains(@OrgId))
|| (oh.OrganizationsId == Id)
select o.Id).ToList();
List<Personnel> query = (from p in this.Database.Personnels
where (OrgIds.Contains(p.OrganizationId))
select p).ToList();
Thanks all,
谢谢大家，
-Matt
-马特
回答by Solmead
It would be something like this, OrgIds.ToList.Contains(p.OrginizationID)
它会是这样的， OrgIds.ToList.Contains(p.OrginizationID)
Though really I would do it more like this:
虽然我真的会这样做：
var OrgIds = (from oh in this.Database.OrganizationsHierarchies
join o in this.Database.Organizations on oh.OrganizationsId equals o.Id
where (oh.Hierarchy.Contains(@OrgId))
|| (oh.OrganizationsId == Id)
select o.Id);
List<Personnel> query = (from p in this.Database.Personnels
where (OrgIds.Contains(p.OrigizationID)
select p).ToList();
That way the final query to get personnel will execute containing the combined query from both.
这样，获取人员的最终查询将包含来自两者的组合查询。
