Typescript / Javascript：将对象数组转换为键，值对

Question

在我的应用程序（React-typescript）中，我有一些类型的文档

interface IDocument {id: string;  questions: IQuestion[];}

interface IQuestion {number: string;  answer: string; }

所以一系列文档看起来像是：

doscuments: IDocument[] = [

  {id: "a",

    questions: [

      { number: "1", answer: "answer1" },

        ... /* more number answer*/

    ]},

  {id: "b",

    questions: [

      { number: "1", answer: "answer1" },

        ... /* more number answer*/

    ]}

];

现在我想将其转换为另一种类型的形式

interface IAlternative {

  [key: string]: string;

}

具有ie的键值对

alterDocs: IAlternative = {a1:"answer1", a2:"answer2",...,b1:"answer1",...}

为此，我有下面的代码，但不能构造doc.id+question.number作为键和question.answer值的对

documents.forEach(doc:IDocument=>{

 doc.questions.forEach(question=>{

    const pair= {} // I cannot construct this pair

    alterDocs={...alterDocs,...pair}

  })

})