LINQ query to find if items in a list are contained in another list

Question

I have the following code:

List test1 = new List { \"@bob.com\", \"@tom.com\" };
List test2 = new List

        

Answer 1

something like this:

List<string> test1 = new List<string> { "@bob.com", "@tom.com" };
List<string> test2 = new List<string> { "joe@bob.com", "test@sam.com" };

var res = test2.Where(f => test1.Count(z => f.Contains(z)) == 0)

Live example: here

Answer 2

List<string> l = new List<string> { "@bob.com", "@tom.com" };
List<string> l2 = new List<string> { "joe@bob.com", "test@bob.com" };
List<string> myboblist= (l2.Where (i=>i.Contains("bob")).ToList<string>());
foreach (var bob in myboblist)
    Console.WriteLine(bob.ToString());

Answer 3

var output = emails.Where(e => domains.All(d => !e.EndsWith(d)));

Or if you prefer:

var output = emails.Where(e => !domains.Any(d => e.EndsWith(d)));

Answer 4

var test2NotInTest1 = test2.Where(t2 => test1.Count(t1 => t2.Contains(t1))==0);

Faster version as per Tim's suggestion:

var test2NotInTest1 = test2.Where(t2 => !test1.Any(t1 => t2.Contains(t1)));

Answer 5

I think this would be easiest one:

test1.ForEach(str => test2.RemoveAll(x=>x.Contains(str)));

Answer 6

No need to use Linq like this here, because there already exists an extension method to do this for you.

Enumerable.Except<TSource>

http://msdn.microsoft.com/en-us/library/bb336390.aspx

You just need to create your own comparer to compare as needed.