Synchronization of ArrayList in C#

Use the ArrayList.Synchronized Method in C# for synchronization of ArrayList in C#.

Let us see an example to lock the collection using SyncRoot property in C# −

ArrayList arr = new ArrayList();
lock(arr.SyncRoot) {
   foreach (object ele in arr) {
   }
}

The following is the complete example to check the synchronization status of ArrayList −

Example

using System;
using System.Collections;
public class Demo {
   public static void Main() {

      ArrayList arr1 = new ArrayList();
      arr1.Add("One");
      arr1.Add("Two");
      arr1.Add("Three");
      arr1.Add("Four");
      arr1.Add("Five");
      arr1.Add("Six");
      arr1.Add("Seven");
      arr1.Add("Eight");

      // set synchronized wrapper around the ArrayList
      ArrayList arr2 = ArrayList.Synchronized(arr1);

      // sychronization status of first ArrayList
      Console.WriteLine("arr1 = {0}", arr1.IsSynchronized ? " synchronized" : "not synchronized");

      // sychronization status of second ArrayList
      Console.WriteLine("arr2 = {0}", arr2.IsSynchronized ? "synchronized" : "not synchronized");
   }
}

Output

arr1 = not synchronized
arr2 = synchronized