Using a Read-Only List

This C# program demonstrates how to create and use a read-only list of elements.

Program.cs

using System;
using System.Collections.Generic;


namespace XoaX {

    class Program {
        static void Main(string[] args) {
            // Allocate a fixed-sized list. This is convenient if we know the size.
            List<string> qTheologicalVirtues = new List<string>(3);

            qTheologicalVirtues.Add("Faith");
            qTheologicalVirtues.Add("Hope");
            qTheologicalVirtues.Add("Love");

            // Create the read-only list
            IList<string> qReadOnlyList = qTheologicalVirtues.AsReadOnly();

            // Display the virtues via the read-only collecion
            Console.WriteLine("Theological Virtues:");
            Console.WriteLine("--------------------");
            foreach (string sVirtue in qReadOnlyList) {
                Console.WriteLine(sVirtue);
            }
            Console.WriteLine("");

            // Change the third entry via the original list.
            qTheologicalVirtues[2] = "Charity";

            // Display the virtues again via the read-only collecion
            Console.WriteLine("Theological Virtues:");
            Console.WriteLine("--------------------");
            foreach (string sVirtue in qReadOnlyList) {
                Console.WriteLine(sVirtue);
            }
            Console.WriteLine("");
        }
    }

}

Output

Theological Virtues:
--------------------
Faith
Hope
Love

Theological Virtues:
--------------------
Faith
Hope
Charity

Press any key to continue . . .