Get the number of distinct property values in List<T> using LINQ in C# -


in list list<myclass> listofmyclasses, how can 1 how many distinct groupid property values there using linq?

public class myclass {      public int groupid; }

for example let's have list:

listofmyclasses: {myclass1 (groupid = 1), myclass2 (groupid = 3), myclass3 (groupid = 1)}

here should result 2 (two distinct numbers groupid).

here 1 way using distinct:

listofmyclasses.select(t => t.groupid).distinct().count()

or can use groupby:

listofmyclasses.groupby(t => t.groupid).count()

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