public static void RandomizeArrayList(ArrayList arrayList, Random random) {
    if(arrayList == null) { return; }
    int count = arrayList.Count;
    for(int i=0;i<count;i++) {
       Object tmp = arrayList[i];
       arrayList.RemoveAt(i);
       arrayList.Insert(random.Next(count), tmp);
    }
 }
//csharp/4866