What is the best way of getting values not found in 2 lists?

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Hi guys,

I am trying to compare the contents of 2 lists and spit out any items in the list not found in both. I am not sure what the best method for this is, i have tried this:

C#

List<object1> list = GetList();
List<object1> list2 = list;

            foreach(list g in list)
            {
                if (!list2.Contains(g))
                {
                    Method1();
                }
            }

Method1 is fires for each item in the list where it shouldnt, do i need a better comparer? object1 is an object with multiple fields.

Regards
Carl

Posted 7-Jul-14 22:43pm

Carl Mailey

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Nguyen.H.H.Dang · Answer 1 · 2014-07-07T23:10:00

Solution 2

Example :
ListA : A,B,C
ListB : A,B,E

=> compare A with B :

List<string> result = ListA.Except(ListB).ToList();

=> result : C

You can read more at this link :

http://stackoverflow.com/questions/12795882/quickest-way-to-compare-two-list[^]

Posted 7-Jul-14 23:10pm

Nguyen.H.H.Dang

DamithSL · Answer 2 · 2014-07-07T23:01:00

Solution 1

Unclear what is your exact requirement, but you can try with linq like below

C#

if(!list.Any(g=>list2.Contains(g))
{
   Method1();
}

Posted 7-Jul-14 23:01pm

DamithSL