如何在C#中重载[]运算符

public class CustomArray
{
    private int[] _array;

    public CustomArray(int size)
    {
        _array = new int[size];
    }
}

public int this[int index]
{
    get { return _array[index]; }
    set { _array[index] = value; }
}

CustomArray customArray = new CustomArray(5);
customArray[0] = 10;
customArray[1] = 20;
customArray[2] = 30;
customArray[3] = 40;
customArray[4] = 50;

for (int i = 0; i < 5; i++)
{
    Console.WriteLine("Element at index {0} : {1}", i, customArray[i]);
}