In JavaScript, we can access the properties of an object using the name of the object followed by a dot and the name of the property:
let foo: any = {};foo.hello = 'World';console.log(foo.hello); // World
However, it is also possible to access the properties of an object using the name of the object followed by the name of the property as a string wrapped by brackets:
let foo: any = {};foo['hello'] = 'World';console.log(foo['hello']); // World
This behavior can be declared using what is known as the index signature:
interface StringArray { [index: number]: string;}let myArray: StringArray = ["Bob", "Fred"];let myStr: string = myArray[0];
As we can see in the preceding code snippet, the index signature allows us to specify ...
