System.ComponentModel.Design.DesignerOptionService.DesignerOptionCollection.this C# (CSharp) Method

            public DesignerOptionCollection this[int index]
            {
                [SuppressMessage("Microsoft.Globalization", "CA1303:DoNotPassLiteralsAsLocalizedParameters")]
                get
                {
                    EnsurePopulated();
                    if (index < 0 || index >= _children.Count)
                    {
                        throw new IndexOutOfRangeException(nameof(index));
                    }
                    return (DesignerOptionCollection)_children[index];
                }
            }