I override a list in VB.

In C# the code compiles and looks like this:

class MyObjectCollection : IList
{
    ...
    /// <summary>
    /// Gets or sets the element at the specified index.
    /// </summary>
    public MyObject this[int index]
    {
        get { return (MyObject)innerArray[index]; }
        set { innerArray[index] = value; }
    }
    ...
}

in VB.NET I transform:

Class MyObjectCollection
    Implements IList        
    ...

    ''' <summary> '
    ''' Gets or sets the element at the specified index. '
    ''' </summary> '
    Default Public Overrides Property Item(ByVal index As Integer) As MyObject
      Get
        Return DirectCast(innerArray(index), MyObject)
      End Get
      Set(ByVal value As MyObject)
        innerArray(index) = value
      End Set
    End Property
    ...
End Class

Error:

'Public Overrides Default Property Item(index As Integer) As MyObject' and 'Public Default Property Item(index As Integer) As Object' cannot overload each other because they differ only by return types

Whole collection class in C#

public class MyObjectCollection : IList
{
    private ArrayList innerArray;

    public MyObjectCollection()
    {
        innerArray = new ArrayList();
    }

    public int Count
    {
        get { return innerArray.Count; }
    }

    public bool IsFixedSize
    {
        get { return false; }
    }

    public bool IsReadOnly
    {
        get { return false; }
    }

    public bool IsSynchronized
    {
        get { return false; }
    }

    object ICollection.SyncRoot
    {
        get { return null; }
    }

    public MyObject this[int index]
    {
        get { return (MyObject)innerArray[index]; }
        set { innerArray[index] = value; }
    }

    public int Add(MyObject value)
    {
        int index = innerArray.Add(value);

        return index;
    }

    public void AddRange(MyObject[] array)
    {
        innerArray.AddRange(array);
    }

    public void Clear()
    {
        innerArray.Clear();
    }

    public bool Contains(MyObject item)
    {
        return innerArray.Contains(item);
    }

    public bool Contains(string name)
    {
        foreach (MyObject spec in innerArray)
            if (spec.Name == name)
                return true;

        return false;
    }

    public void CopyTo(MyObject[] array)
    {
        innerArray.CopyTo(array);
    }

    public void CopyTo(MyObject[] array, int index)
    {
        innerArray.CopyTo(array, index);
    }

    public IEnumerator GetEnumerator()
    {
        return innerArray.GetEnumerator();
    }

    public int IndexOf(MyObject value)
    {
        return innerArray.IndexOf(value);
    }

    public int IndexOf(string name)
    {
        int i = 0;

        foreach (MyObject spec in innerArray)
        {
            if (spec.Name == name)
                return i;

            i++;
        }

        return -1;
    }

    public void Insert(int index, MyObject value)
    {
        innerArray.Insert(index, value);
    }

    public void Remove(MyObject obj)
    {
        innerArray.Remove(obj);
    }

    public void Remove(string name)
    {
        int index = IndexOf(name);
        RemoveAt(index);
    }

    public void RemoveAt(int index)
    {
        innerArray.RemoveAt(index);
    }

    public MyObject[] ToArray()
    {
        return (MyObject[])innerArray.ToArray(typeof(MyObject));
    }

    #region Explicit interface implementations for ICollection and IList
    void ICollection.CopyTo(Array array, int index)
    {
        CopyTo((MyObject[])array, index);
    }

    int IList.Add(object value)
    {
        return Add((MyObject)value);
    }

    bool IList.Contains(object obj)
    {
        return Contains((MyObject)obj);
    }

    object IList.this[int index]
    {
        get
        {
            return ((MyObjectCollection)this)[index];
        }
        set
        {
            ((MyObjectCollection)this)[index] = (MyObject)value;
        }
    }

    int IList.IndexOf(object obj)
    {
        return IndexOf((MyObject)obj);
    }

    void IList.Insert(int index, object value)
    {
        Insert(index, (MyObject)value);
    }

    void IList.Remove(object value)
    {
        Remove((MyObject)value);
    }
    #endregion
}