Filtering from 2 collections C#

Question

There are 2 collections. Coll A is items = {1,2,3,4,5}. Coll B = { 3, 6, 7 } Need to find the common item and then remove all the other items from Coll A. So the result is this example should be Coll A = { 3 }.

Can you a please let me know a Simple and elegant way..

Thanks

In the real world, we'd use `Intersect()`. However, if this is homework s/he will probably not accept that... you'll have to put some thought into it and roll out your own ;) — BlueRaja - Danny Pflughoeft, May 23 '11 at 03:24

score 4 · Accepted Answer · answered May 23 '11 at 03:22

4

You can you use the LINQ Intersect method:

collectionA = collectionA.Intersect(collectionB).ToList();

answered May 23 '11 at 03:22

dlev

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Another instance is where I have a object and there is list of ID's that get passed. How do I remove the rows corresponding to these Id's – Andy May 23 '11 at 04:22

score 0 · Answer 2 · answered May 23 '11 at 03:22

0

Try this: http://msdn.microsoft.com/en-us/vcsharp/aa336761.aspx#intersect1. LINQ provides a method called Intersect which operates the same as a mathematical intersection of two sets should.

answered May 23 '11 at 03:22

Tieson T.

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Another instance is where I have a object and there is list of ID's that get passed. How do I remove the rows corresponding to these Id's – Andy May 23 '11 at 03:54
@Andy You really should be posting a new question. However, I think this should help you [http://stackoverflow.com/questions/853526/c-using-linq-to-remove-objects-within-a-listt](http://stackoverflow.com/questions/853526/c-using-linq-to-remove-objects-within-a-listt) – Tieson T. May 26 '11 at 03:53

Filtering from 2 collections C#

2 Answers2