C#Linq查询:从列表中获取键在其他列表中的所有项目

问题描述：

我有两个列表集合.一个带有键，另一个带有记录.

I have two list collections. One with keys and one with records.

class Record
{
int key;
string Data;
}

List<int> Keys = new List<int>{1,2,3};

List<record> records = [SOME_RECORDS]
</record></int></int>

如何从记录"列表中获取所有项，其中键"列表中的键属性是什么?

How to get all items from Records list which key property is in Keys list?
Could it be one line linq expression?

答

使用您的代码，我会这样做:

Using your code, I''d do it like this:

var results = records.Where(r => Keys.Contains(r.key));

或者您也可以通过联接来执行此操作，以防添加更多条件，例如:

Or you can also do this with a join in case you want to add more conditions etc:

var query = from record in records
            join key in Keys on record.key equals key
            select record;

如果同一条记录可以有多个键，则可以使用Distinct操作

In case you can have multiple keys for the same record, you can use the Distinct operation