Insert more than one element at once in a C# List

Use the InsertRange() method to insert a list in between the existing lists in C#. Through this, you can easily add more than one element to the existing list.

Let us first set a list −

List<int> arr1 = new List<int>();
arr1.Add(10);
arr1.Add(20);
arr1.Add(30);
arr1.Add(40);
arr1.Add(50);

Now, let us set an array. The elements of this array are what we will add to the above list −

int[] arr2 = new int[4];
arr2[0] = 60;
arr2[1] = 70;
arr2[2] = 80;
arr2[3] = 90;

We will add the above elements to the list −

arr1.InsertRange(5, arr2);

Here is the complete code −

Example

 Live Demo

using System;
using System.Collections.Generic;
public class Demo {
   public static void Main() {
      List<int> arr1 = new List<int>();
      arr1.Add(10);
      arr1.Add(20);
      arr1.Add(30);
      arr1.Add(40);
      arr1.Add(50);
      Console.WriteLine("Initial List ...");
      foreach (int i in arr1) {
         Console.WriteLine(i);
      }
      int[] arr2 = new int[4];
      arr2[0] = 60;
      arr2[1] = 70;
      arr2[2] = 80;
      arr2[3] = 90;
      arr1.InsertRange(5, arr2);
      Console.WriteLine("After adding elements ...");
      foreach (int i in arr1) {
         Console.WriteLine(i);
      }
   }
}

Output

Initial List ...
10
20
30
40
50
After adding elements ...
10
20
30
40
50
60
70
80
90