Is it possible to destructure instance/member variables in a JavaScript constructor?

Question

Is it possible to use destructuring assignment in a JavaScript class\' constructor to assign the instance variables similar to how you can do it to normal variables?

The

Answer 1

There are multiple ways of doing this. The first one uses destructuring only and assigns the properties of options to properties on this:

class Foo {
  constructor(options) {
    ({one: this.one, two: this.two} = options);
    // Do something else with the other options here
  }
}

The extra parentheses are needed, otherwise the JS engine might mistake the { ... } for an object literal or a block statement.

The second one uses Object.assign and destructuring:

class Foo {
  constructor(options) {
    const {one, two} = options;
    Object.assign(this, {one, two});
    // Do something else with the other options here
  }
}

If you want to apply all your options to the instance, you could use Object.assign without destructuring:

class Foo {
  constructor(options) {
    Object.assign(this, options);
  }
}