Javascript 获取API存储自定义头值以供以后使用

我有以下资料：

let eTag: any 

const request = (method: string) => (basePath: string) => async (path: string, data?: object) => {
  const accessToken = await getAccessToken()
  const opt: any = {
    method,
    headers: {
      Authorization: `Bearer ${accessToken}`,
      ...(data && { eTag })
    },
    ...(data && { body: data }),
  }

  return fetch(`${basePath}${path}`, opt).then(
    res => {
      eTag = res.headers.get('ETag')

      return res.json()
    }
  )
}

let eTag: any 

const request = (method: string) => (basePath: string) => async (path: string, data?: object) => {
  const accessToken = await getAccessToken()
  const opt: any = {
    method,
    headers: {
      Authorization: `Bearer ${accessToken}`,
      ...(data && { eTag })
    },
    ...(data && { body: data }),
  }

  return fetch(`${basePath}${path}`, opt).then(
    async res => { //add async keyword
      eTag = res.headers.get('ETag')

      return await res.json() //add await here to return resolved json
    }
  )
}

我已经设法从客户标题

eTag

中获取了值，但它似乎没有正确存储它

我得到的错误是关于

res.JSON（）

res.JSON（）

返回一个错误。因此，您需要以下内容：

let eTag: any 

const request = (method: string) => (basePath: string) => async (path: string, data?: object) => {
  const accessToken = await getAccessToken()
  const opt: any = {
    method,
    headers: {
      Authorization: `Bearer ${accessToken}`,
      ...(data && { eTag })
    },
    ...(data && { body: data }),
  }

  return fetch(`${basePath}${path}`, opt).then(
    res => {
      eTag = res.headers.get('ETag')

      return res.json()
    }
  )
}

let eTag: any 

const request = (method: string) => (basePath: string) => async (path: string, data?: object) => {
  const accessToken = await getAccessToken()
  const opt: any = {
    method,
    headers: {
      Authorization: `Bearer ${accessToken}`,
      ...(data && { eTag })
    },
    ...(data && { body: data }),
  }

  return fetch(`${basePath}${path}`, opt).then(
    async res => { //add async keyword
      eTag = res.headers.get('ETag')

      return await res.json() //add await here to return resolved json
    }
  )
}

---

你也可以粘贴你的json吗？