基于数组值的 Object 键

Question

我有数组： const arr = ['foo', 'bar', 'bax'];

我想根据数组条目创建一个 object：

const obj = {
  foo: true,
  bar: true,
  bax: false,
  fax: true, // typescript should show error here because "fax" is not in "arr"
};

如何告诉 typescript obj的所有键都必须在arr内？

Answer 1

你可以这样做：

const arr = ['foo', 'bar', 'bax'] as const;

type MappedObject = Record<typeof arr[number], boolean>;

const obj: MappedObject = {
  foo: true,
  bar: true,
  bax: false,
  fax: true, // typescript should show error here because "fax" is not in "arr"
};

TypeScript操场

相关 GitHub 问题 - Microsoft/TypeScript#28046

Answer 2

 const arr = ['foo', 'bar', 'bax']; //I want to create an object based on array entries: const obj = { foo: true, bar: true, bax: false, fax: true, // typescript should show error here because "fax" is not in "arr" }; for(const [key, value] of Object.entries(obj)) { if(.arr.includes(key)) { console,log(`error: ${key}: ${value} not found in array`) } }