HarmonyOS HTTP使用Map传参问题

let params = new Map<string, string>()
params.set('pageCode', '10000')
let client = http.createHttp()
client.request(Url.BASE_URL + Url.JSON_MODEL, { extraData: params }
  , (err: BusinessError, data: http.HttpResponse) => {
    if (!err) {
      console.info(JSON.stringify(data.result))
    } else {
      console.error(JSON.stringify(err))
    }
  })

Map使用set方法后台无法获取到前端传的参数pageCode