List out the decorators

Question

List out the decorators

One query is bothering me - I am attempting to create my own version of Injectable and I need to determine if a specific decorator exists in my Class. Is there a way to list all decorators of a class? Let's take the example below. All I want to know is whether "myDecorator" is present as a decorator in MyClass or not.

function myDecorator(ctor: Function):void{
    console.log(ctor)}

@myDecorator

class MyClass{
    static isInjectable: boolean;
    public a: number = 5;
    constructor() {
        this.a = 5;
    }
}

I wonder if using the Reflect-API could help solve this problem, although I haven't figured out how to use it properly yet.

typescript typescript-decorator

Answer 1

Answer №1

To achieve the desired functionality, you should create a decorator as shown below:

export function MyDecorator(constructor: Function): void{
    Reflect.defineMetadata("isMyDecorator", MyDecorator, constructor);
}

export class MyInjector<T>{
    get(ctor: {new() : T}): T{
        console.log(Reflect.getMetadata("isMyDecorator", ctor));
            return new ctor();
    }
}

Next step would be to access it through the MyInjector class.

Answer 2

To achieve the desired functionality, you should create a decorator as shown below:

export function MyDecorator(constructor: Function): void{
    Reflect.defineMetadata("isMyDecorator", MyDecorator, constructor);
}

export class MyInjector<T>{
    get(ctor: {new() : T}): T{
        console.log(Reflect.getMetadata("isMyDecorator", ctor));
            return new ctor();
    }
}

Next step would be to access it through the MyInjector class.

List out the decorators

Answer №1

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