LINQ: List of Unique Names

Question

(Simplified)

I have a list of full name Strings. The first 6 characters are the first name always.

List<string>()
  fredXXsmith
  aliceXFloor
  billXXjohnson
  fredXXperterson

How can I get the list of unique first names from these strings in LINQ?

  fredXX 
  aliceX 
  billXX

This might be a bit old, but it could still be useful: [http://stackoverflow.com/a/1300116/1026130](http://stackoverflow.com/a/1300116/1026130) — , Mar 12 '13 at 19:45

score 4 · Accepted Answer · answered Mar 12 '13 at 19:43

You just need to project the full names to the substrings, and then use Distinct:

var firstNames = names.Select(x => x.Substring(0, 6))
                      .Distinct();

This is assuming (given your example) that you always have at least 6 characters (padded with X). Add a ToList call to the end of the chain if you want a List<string>.

score 3 · Answer 2 · answered Mar 12 '13 at 19:44

3

names.Select(fullName => fullName.Substring(0, 6)).Distinct();

Substring gets you the first six characters, and Distinct gives you unique results.

answered Mar 12 '13 at 19:44

Bort

7,398
3
33
48

score 2 · Answer 3 · answered Mar 12 '13 at 19:46

2

names.Select(x => x.Substring(0,6)).Distinct()

answered Mar 12 '13 at 19:46

Khan

17,904
5
47
59

LINQ: List of Unique Names

3 Answers3