Is following Indexer property possible?

Question

Suppose I have an array or any other collection for that matter in class and a property which returns it like following:

public class Foo
{
    public IList<Bar> Bars{get;set;}
}

Now, may I write anything like this:

public Bar Bar[int index]
{
    get
    {
        //usual null and length check on Bars omitted for calarity
        return Bars[index];
    }
}

Answer 1

Depending on what you're really looking for, it might already be done for you. If you're trying to use an indexer on the Bars collection, it's already done for you::

Foo myFoo = new Foo();
Bar myBar = myFood.Bars[1];

Or if you're trying to get the following functionality:

Foo myFoo = new Foo();
Bar myBar = myFoo[1];

Then:

public Bar this[int index]
{
    get { return Bars[index]; }
}

Answer 2

No - you can't write named indexers in C#. As of C# 4 you can consume them for COM objects, but you can't write them.

As you've noticed, however, foo.Bars[index] will do what you want anyway... this answer was mostly for the sake of future readers.

Answer 3

You can roll your own "named indexer" however. See

• http://stackoverflow.com/questions/2806894/why-c-doesnt-implement-indexed-properties
• http://stackoverflow.com/questions/3344620/easy-creation-of-properties-that-support-indexing-in-c