Indexer:Why to use it if Public array can solve the purpose

Question

1. If public array can solve the purpose, then why to use indexer 2.There is array member private int [] myArray = new int[100]; in class say c1. I have used the following code to use indexer public int this [int index] // Indexer declaration { get { // Check the index limits. if (index < 0 || index >= 100) return 0; else return myArray[index]; } set { if (!(index < 0 || index >= 100)) myArray[index] = value; } } It is working fine. But say there is another member private string [] myArray11 = new string[100]; in the same class along with previous member, then how to use indexer for it.