Create object from class name in JavasScript ECMAScript 6

Question

I want create object factory using ES6 but old-style syntax doesn\'t work with new.

I have next code:

export class Column {}
export class Sequence {}         


        

Answer 1

The problem is that the classes are not properties of the window object. You can have an object with properties "pointing" to your classes instead:

class Column {}
class Sequence {}
class Checkbox {}
let classes = {
  Column,
  Sequence,
  Checkbox 
}

class ColumnFactory {
    constructor() {
        this.specColumn = {
            __default: 'Column',
            __sequence: 'Sequence',
            __checkbox: 'Checkbox'
        };
    }

    create(name) {
        let className = this.specColumn[name] ? this.specColumn[name] : this.specColumn['__default'];
        return new classes[className](name); // this line no longer throw error
    }
}

let factory = new ColumnFactory();
let column = factory.create('userName');

export {ColumnFactory, Column, Sequence, Checkbox};