Implementing an indexer in a class in TypeScript

Question

Is it currently possible to implement an indexer on a class in TypeScript?

class MyCollection {    [name: string]: MyType;        } 

This doesn't compile. I can specify an indexer on an interface, of course, but I need methods on this type as well as the indexer, so an interface won't suffice.

Thanks.

Answer 1

You cannot implement a class with an indexer. You can create an interface, but that interface cannot be implemented by a class. It can be implemented in plain JavaScript, and you can specify functions as well as the indexer on the interface:

class MyType {     constructor(public someVal: string) {      } }  interface MyCollection {       [name: string]: MyType; }  var collection: MyCollection = {};  collection['First'] = new MyType('Val'); collection['Second'] = new MyType('Another');  var a = collection['First'];  alert(a.someVal);