Accessing object property when object consists of classes-CodePudding

With an object consisting of references to classes:

// commands/index.ts
export default {
  Authorize,
  BootNotification,
  ...
  UpdateFirmware,
};

How do I go about creating variables and instantiate dynamically from this object? For something like bellow I get the ts error:

TS2538: Type '{ Authorize: typeof Authorize; BootNotification: typeof BootNotification; CancelReservation: typeof CancelReservation; ChangeAvailability: typeof ChangeAvailability; ... 23 more ...; UpdateFirmware: typeof UpdateFirmware; }' cannot be used as an index type.

Code:

import commands from "./commands"; 
let commandNameOrPayload: typeof commands;
let commandPayload: any;
let CommandModel: typeof commands;

CommandModel = commands[commandNameOrPayload];
commandRequest = new CommandModel(commandPayload);

For the last line of newCommandModel I'm getting the error: TS2351: This expression is not constructable.

CodePudding user response：

The classes from your commands export are indexed by the string representation of their name, so in order to access them, your commandNameOrPayload also needs to be of type string:

class A {/**bla**/}

class B {/**bla**/}

let commands = {
  A,
  B
}

console.log(commands["A"]) // will log class A {}
let command = new commands["A"];

console.log(command instanceof A)

See my playground: https://tsplay.dev/wjkrbN