Retrieving class properties in typescript

I am working with a class that has numerous methods, which I refer to as myClass. When calling it, the syntax is as follows:

myClass[key]()

Is there a way to retrieve the valid values for key? I tried using keyof myClass, but received an error message stating 'myClass refers to a value, but is being used as a type here'

The issue may stem from the fact that myClass is currently defined in a .js file and encapsulated like this:

const myClass = new MyActualClass();
export default myClass

Is there a method to extract this information without converting the .js file to TypeScript and accessing the details directly from MyActualClass?

typescriptclassmethods

Answer №1

If you're looking to access the dynamic property names, one way is by utilizing either Object.keys or Object.getOwnPropertyNames.

In TypeScript, suppose you want to define a variable that can store the keys for an object of your class, the syntax would be as follows:

let key: keyof typeof myClass;

Check out this playground example for better understanding.

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

Expressions without a call signature cannot be invoked

When using an adapter in the given example, I encountered a type error specifically on the last line of the getGloryOfAnimal method. Despite having clearly defined types, I am puzzled by this issue. interface ICheetah { pace: string; } interface ILio ...

typescripttypescript2.0

Tips for validating Enum Strings using the newest version of Joi?

Is there a way to validate Enum String? In the past, I followed this advice from: https://github.com/hapijs/joi/issues/1449 enum UserRole { Admin = 'admin', Staff = 'staff' } const validator = { create: Joi.object().keys({ ...

javascriptnode.jstypescriptexpress

Combining Vue-Test-Utils with TypeScript typings for wrapper.vm

So, I ran into an interesting situation. Has anyone ever worked with typescript + vue-test-utils and attempted to change a value for testing purposes like this: wrapper.vm.aCoolRefValueToManipulate = 'something much cooler'? I gave it a shot, a ...

typescriptvue.jsvue-test-utilstypescript-eslintvitest

Testing a reusable component in Angular using unit testing techniques

Currently, I am creating a test for an AppleComponent which has the following type: <T,U extends BananaComponent<T>>. This component also contains BananaComponent<T>. Target Component export class AppleComponent<T,U extends BananaCom ...

angulartypescriptunit-testing

Angular 2 signal sender

I have a specific class definition for my Project: export class Project { $key: string; file: File; name: string; title: string; cat: string; url: string; progress: number; createdAt: Date = new Date(); constructor(file: File) { th ...

javascriptangulartypescriptfirebase

What is the best way to use lodash to group objects that contain nested objects?

Currently utilizing Typescript in conjunction with Lodash! Upon retrieving data from the database, here is the resulting output: [ { "unitPrice": 0.01, "code": "92365524", "description": "Broto gr ...

javascriptnode.jstypescriptlodash

Enclose the type definition for a function from a third-party library

I prefer to utilize Typescript for ensuring immutability in my code. Unfortunately, many libraries do not type their exported function parameters as Readonly or DeepReadonly, even if they are not meant to be mutated. This commonly causes issues because a ...

typescripttypescript-typingstypescript-generics

What causes an increase in the size of an object when a class utilizes virtual inheritance?

In this particular block of code: #include <iostream> class a { char a; }; class b : virtual public a { char b; }; class c : virtual public a { char c; }; class d : public b, public c { char d; }; int main() { std::cout < ...

c++classinheritancevirtual

Learn how to trigger an event or API call in Angular 8 when the browser is closed with the help of HostListener

I am facing the challenge of calling a simple websocket closure API when the browser is closed in my project. I attempted to utilize HostListener, but unfortunately it did not work as expected. You can find the code snippet below: https://stackblitz.com/ ...

angulartypescript

Caution in NEXTJS: Make sure the server HTML includes a corresponding <div> within a <div> tag

Struggling with a warning while rendering pages in my Next.js and MUI project. Here's the code, any insights on how to resolve this would be greatly appreciated! import "../styles/globals.scss"; import { AppProps } from "next/app"; ...

reactjstypescriptmaterial-uinext.jsserver-side-rendering

Exploring Typescript Reflection: The Importance of Required Parameters and Default Values

In summary: Is there a method to determine whether a typescript parameter is mandatory and/or has a preset value? Expanding further: Imagine I have the code snippet below: //Foo.ts class Bar { foo(required:string,defaultValue:number=0,optional?:boole ...

reflectiontypescriptoptional-parameters

Creating a custom extended version of Angular2 Http does not automatically provide injection of services

I'm struggling to understand this issue. I've created a custom class that extends Angular's Http class. import { Injectable } from '@angular/core'; { Http, ConnectionBackend, RequestOptions, RequestOptionsArgs, ...

angulartypescriptecmascript-6ionic2

Determining the name of the currently focused DOM element in Angular2

How can I detect the name of a selected element from a group of select elements on a page? For example: <select (click)="functionDetectName()" name="test1"> <select (click)="functionDetectName()" name="test2"> <select (click)="functionDete ...

angulartypescript

What is the approach taken by this component to display its child elements?

While delving into the code of react-accessible-accordion, I found myself puzzled by the way it handles rendering its children. The snippet below is from Accordion.tsx: export default class Accordion extends React.Component<AccordionProps> { // ...

reactjstypescript

Karma Test Requirement: make sure to incorporate either "BrowserAnimationsModule" or "NoopAnimationsModule" when using the synthetic property @transitionMessages within your application

TEST FILE import { async, ComponentFixture, TestBed } from '@angular/core/testing'; import { BrowserAnimationsModule } from '@angular/platform- browser/animations'; import { ManagePageComponent } from './manage-page.component& ...

javascriptangulartypescriptangular-clikarma-jasmine

Angular 2: A guide to setting up `--module system --experimentalDecorators` flags in your project

I am encountering an issue while compiling my TypeScript file: app/app.component.ts import {Component} from 'angular2/core'; @Component({ selector: 'my-app', template: '<h1>Messenger</h1>' }) export clas ...

typescriptangularrubymine

Could you confirm if this is a TypeScript function?

Recently, while delving into the vue-next source code, I stumbled upon a particular line that left me puzzled. Due to my limited experience with TypeScript, I found myself struggling to grasp its purpose. Could someone clarify if this snippet constitutes ...

javascripttypescriptvue.jsvuejs3

How to detect a click event in any area of an Angular2

Hey there, I'm new to typescript and angular 2 and I've encountered an error in my code. Can someone lend me a hand in fixing this? import { Component, HostListener } from '@angular/core' export class TooltipComponent { public sh ...

javascriptangulartypescript

Can you use TypeScript to define generic React functional components?

I am looking to add annotations to a generic in a React functional component like the following: import React, {useEffect, useState} from "react"; interface PaginatedTableProps{ dataFetcher: (pageNumber: number) => Promise<any>, columnNames: ...

javascriptreactjstypescripttypescript-genericsreact-typescript

type Y does not contain property X

When I encounter this error message: The property 'module' is missing in the type 'Menu'. The property 'parentId' is not found in the type 'Menu'. the code snippet triggering it appears like this: private menus: ...

angulartypescript