Without using Distinct(), How to get Distinct List ?

Veerendra Annigere

I have a List of Objects,

var distinctList = someList.DistinctBy(x => x.Prop2).ToList();

Need to get distinct list without using distinct.

4 Replies

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Sachin Singh5y ago
By selecting the First Group, you will always get distinct.
var distinctList = someList.GroupBy(x=>x.Prop2).Select(g=>g.First());
+1
Madan Shekar5y ago
Hi ,

In this case we can apply Union logic : set's operations

here is the sample code
using System;
using System.Collections.Generic;
using System.Linq;

class Demo {
   static void Main() {

      List<int> val1 = new List<int> { 25, 30, 40, 60, 80, 95, 110 };
      List<int> val2 = new List<int> { 27, 35, 40, 75, 95, 100, 110 };

      IEnumerable<int> res = val1.AsQueryable().Union(val2);

      Console.WriteLine("Union of both the lists...");
      foreach (int a in res) {
         Console.WriteLine(a);
      }
   }
}
+1
Basem Alshabani5y ago
Var list=(From xtuples in x group by x.Name Select x.first()).ToList() Note:replace name with your class property name
+1
Priyanka K S5y ago
you can try using GroupBy
var distinctList = someList.GroupBy(elem=>elem.Prop2).Select(group=>group.First());
+2