Comparing two lists distinct value C#

Question

I have 2 lists say list1 and list2. Like

 List<int> list1 = {1,2,3};
 List<int> list2 = {3,4};

now I want my resultant list to be like

{1,2,3,4}

I have tried this

result= list1.Union(list2).ToList();

But it gives result like

{1,2,3,3,4}

Can anyone help me with this?

Please post a [mcve], I cannot reproduce the behavior you're describing, what you're describing is the result of calling `.Concat`, not `.Union`, the behavior of `.Union` is exactly what you say you want. As such, you must post a [mcve] so that we can see exactly what you're doing. — Lasse V. Karlsen, Feb 02 '17 at 07:42
Possible you have lists of objects that do not implement `IComparable` — Gene R, Feb 02 '17 at 07:45
Your code returned `{1,2,3,4}` when I tested it. Is it really what you are doing? — Guy, Feb 02 '17 at 07:45
Please bear in mind that if you're not *actually* comparing numbers, but your own types, you must override `GetHashCode` and `Equals` in order for `.Union` to know how to compare your types. However, in the specific example you've posted, the code already does what you want it to do. — Lasse V. Karlsen, Feb 02 '17 at 07:46

score 2 · Answer 1 · answered Feb 02 '17 at 07:37

2

It's simple:

var result= list1.Union(list2).Distinct().ToList();

answered Feb 02 '17 at 07:37

Maksim Simkin

1

In the example given there should be no need for `.Distinct()` as the wanted behavior is exactly what `.Union` does. – Lasse V. Karlsen Feb 02 '17 at 07:43

1 Answers1