Generating C# indexers

C# introduces a new concept known as indexers, which are used for treating an object as an array. Indexers are usually known as smart arrays in the C# community.

An indexer is a member that enables objects to be indexed in the same way as an array. An indexer is declared like a property except that the name of the member is "this" followed by a parameter list written between the delimiters [ and ]. The parameters are available in the accessor(s) of the indexer. Similar to properties, indexers can be read-write, read-only, and write-only, and the accessor(s) of an indexer can be virtual.

Indexers can be overloaded, meaning that a class can declare multiple indexers as long as the number or types of their parameters differ.
Indexers are modeled through a UML class with two operations, "get" and "set", to which the <<CsIndexer>> stereotype is added.

A class stereotyped <<CsIndexer>> will not be generated. It will simply be used to generate C# indexer get and set signatures and bodies.

The following is a description of indexer accessors:

· "get": The "get" operation has parameter(s). This (these) parameter(s) allow the indexed research in your array.

· "set": The "set" operation has at least two parameters, and must have the value to set for the right-hand parameter.

These functions help to resolve the indexer signature. Indexer signatures are as follows:

Indexer-visibilityindexer-returnType this[indexer-parameters] { … }

"indexer-visibility" is defined by the class visibility.

"indexer-returnType" is defined by the "get" operation return parameter or by the "set" operation right-hand parameter.

"indexer-Parameters" are defined by the "get" operation parameter(s) or by the "set" operation parameters except the right-hand one, corresponding to the value to be defined.

UML model	C# generated
	using System; using System.Collections; namespace csIndexerSample { public class cImageContainer { public ArrayList images = new ArrayList(); /* cMyIndexer */ public string this[int index] { get { return images.GetValue(index); } set { images.SetValue(index, value); } } } }

Note 1: Embedded classes cannot be visualized in Objecteering Modeler.

Note 2: Generation only takes the "get" and "set" operations of a "CsIndexer" and discards everything else.