C# Linq query: Get all items from list which key is in other list

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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>

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

Posted 10-Apr-11 23:52pm

Updated 10-Apr-11 23:59pm

v2

2 solutions

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;

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

Posted 11-Apr-11 6:23am

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jim lahey · Accepted Answer · 2011-04-11T00:34:00

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

C#

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

Posted 11-Apr-11 0:34am

Comments

Kim Togo 11-Apr-11 7:11am

Agree, the power of LINQ :-)

Umesh AP 15-Mar-16 6:31am

Gr8