Check if List<List<string>> contains a string

Question

How can I check if any List<string>s in a List contain a given string? I know how to do this with a loop, but is there a way with LINQ/in one line?

Answer 1

if (lists.Any(sublist => sublist.Contains(str)))

Answer 2

var t=lists.SelectMany(f=>f).Contains("str");

full sample :

var lists = new List<List<string>>();

lists.Add(new List<string>(){"a","b"});
lists.Add(new List<string>(){"b","2"});
lists.Add(new List<string>(){"c","5"});
lists.Add(new List<string>(){"d","7"});

var t=lists.SelectMany(f=>f);

t.Dump();

if (t.Contains("k")) 
  Console.WriteLine ("yes") ;
else 
  Console.WriteLine ("no");

result

no

p.s.

ofcourse - this can be shorten to :

if (lists.SelectMany(f=>f).Contains("k"))...