TypeScript Objects as Dictionary types as in C#

Question

I have some JavaScript code that uses objects as dictionaries; for example a 'person' object will hold a some personal details keyed off the email address.

var people = {<email> : <'some personal data'>};  adding   > "people[<email>] = <data>;"  getting  > "var data = people[<email>];"  deleting > "delete people[<email>];" 

Is it possible to describe this in Typescript? or do I have to use an Array?

Answer 1

In newer versions of typescript you can use:

type Customers = Record<string, Customer> 

In older versions you can use:

var map: { [email: string]: Customer; } = { }; map['[email protected]'] = new Customer(); // OK map[14] = new Customer(); // Not OK, 14 is not a string map['[email protected]'] = 'x'; // Not OK, 'x' is not a customer 

You can also make an interface if you don't want to type that whole type annotation out every time:

interface StringToCustomerMap {     [email: string]: Customer; }  var map: StringToCustomerMap = { }; // Equivalent to first line of above