c# add to array

var Freds = new [] { "Fred", "Freddy" };
Freds = Freds.Concat(new [] { "Frederick" }).ToArray();int[] arrayOfNumbers = new int[400];
for (int index = 0; runs < 400; runs++)
{
  	// Using array[index], you can modify the value at that index
    arrayOfNumbers[index] = value;
}// To add a value to a C# array, use 'Add()'
List<string> ls = new List<string>();
ls.Add("Hello");List<int> add_list= new List<int>();
for (int i = 0; i < 400; i++)
{
   add_list.Add(value);
}