仅当嵌套 object 具有值时，如何解构它？

Question

  let notStudent, name, isRegistered
  if (studentDetail && studentDetail.fields) {
    ({ notStudent, name, isRegistered } = studentDetail.fields)
  }

Is there a way to write this logic without an if statement or in a succinct way?

Answer 1

You can destructure in this way. The tricky thing is when there is no fields property on studentDetail then javascript can throw an error, to tackle that case, you can set default empty object using || operator.

 let studentDetail = { fields: { notStudent: '1', name: '2', isRegistered: true } } let { notStudent, name, isRegistered } = (studentDetail && studentDetail.fields) || {}; console.log(notStudent); console.log(name); console.log(isRegistered);

Answer 2

You can destructure an empty default object in case your studentDetail.fields doesn't exist:

const { notStudent, name, isRegistered } = studentDetail?.fields ?? {};