How to get class name without instance in Typescripts

Question

I'd like to get class name without instance. But it does not work well. Here is my test code.

class User {
    id!:number;
    name!:string
}

//It should use object type. Not used User type directly.
const run = (o:object) => {
    console.log(o.constructor.name);
}

run(User); 
//It printed as Function. 
//But, I'd like to class name(aka, User) without instance(new User)

How can I do?

Does this answer your question? Get an object's class name at runtime — Jeffrey Ram
– Jeffrey Ram, Commented Aug 24, 2022 at 1:41

Jeffrey Ram · Accepted Answer · 2022-08-24 02:36:00Z

1

Use o.name instead of o.constructor.name

class User {
    id!:number;
    name!:string
}

const run = (o: any) => {
    console.log(o.name);
}

run(User);

Source: Get an object's class name at runtime

edited Aug 24, 2022 at 2:36

answered Aug 24, 2022 at 1:37

Jeffrey Ram

1,1681 gold badge11 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

sean s Over a year ago

When I tested it in my test code(I've linked it in my question), it occur error as "Property 'name' does not exist on type 'object'."

Jeffrey Ram Over a year ago

@seans One way to work around it would be to use type any instead of object like so: const run = (o:any) => {...}

Jeffrey Ram Over a year ago

If you want it to work for both instances and non-instances, refer to @RahulSharma answer below. I excluded the solution for instances because you said "I'd like to get class name without instance."

Rahul Sharma · Accepted Answer · 2022-08-24 02:27:35Z

1

If o is an object use o.constructor.name otherwise o.name.

class User {
    public name: string;

    constructor(name: string) {
        this.name = name;
    }
}

const run = (o: any) => {
    typeof o === 'object' ? console.log(o.constructor.name) : console.log(o.name);
}

run(User);                     // 'User'
run(new User('john doe'));     // 'User'

answered Aug 24, 2022 at 2:27

Rahul Sharma

6,0555 gold badges32 silver badges54 bronze badges

Collectives™ on Stack Overflow

How to get class name without instance in Typescripts

2 Answers 2

3 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related