How to select values which are inside list of list in C#? [duplicate]

Question

I have a list of the object inside a list. I want a list of objects based on some condition.

List<List<int>> lists = new List<List<int>> {
    new List<int> {1, 2, 3},
    new List<int> {4, 5, 6},
    new List<int> {7, 8, 9},
};

If I do something like

lists.Select(x => x.Where(y => y < 5));

I will get a List<List<int>>

But, I actually want List. How can I get all the elements smaller than 5 as a List<int>?

PS: I know I can use for loop, but that's not what I want.

Does this answer your question? Difference Between Select and SelectMany — Preben Huybrechts
– Preben Huybrechts, Commented Jul 14, 2020 at 18:49
Now, it makes sense after reading the answer. I was not sure how to use Where() with SelectMany(). Thanks! — Avadh Vashisth
– Avadh Vashisth, Commented Jul 14, 2020 at 18:58

Manprit Singh Sahota · Accepted Answer · 2020-07-14 18:51:01Z

1

You can utilize SelectMany function provided by linq

var result = lists.SelectMany(x => x).Where(y => y < 5).ToList();

answered Jul 14, 2020 at 18:51

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1 Comment

This is good. Thanks!