C# LINQ find duplicates in List

Question

Using LINQ, from a List, how can I retrieve a list that contains entries repeated more than once and their values?

Answer 1

there is an answer but i did not understand why is not working;

var anyDuplicate = enumerable.GroupBy(x => x.Key).Any(g => g.Count() > 1);

my solution is like that in this situation;

var duplicates = model.list
                    .GroupBy(s => s.SAME_ID)
                    .Where(g => g.Count() > 1).Count() > 0;
if(duplicates) {
    doSomething();
}