javascript - 通过值数组定义接口(interface)

Question

如果我有一个带有输入 props 的常量和一个返回输入 id 及其默认值的函数，如下所示:

const Inputs = [{label: "myInput1", id: "myId1"}, {label: "myInput2" , id: "myId2" }]
    
const getInputValues = () => Inputs.reduce( (acc, item) => ({...acc, [item.id] : 123  }), {} )

如何在 TypeScript 中定义 getInputValues 的返回类型？

Code

Answer 1

我能想到的唯一方法是对您的 Inputs 常量使用 const 断言:

const Inputs = [
  {label: "myInput1", id: "myId1"},
  {label: "myInput2", id: "myId2"},
] as const;

type InputIds = typeof Inputs[number]['id'];

function getInputValues(): Record<InputIds, number> {
  return Inputs.reduce((acc, item) => {
    return {...acc, [item.id]: 123};
  }, {} as Partial<Record<InputIds, number>>) as Record<InputIds, number>;
}