如何從 json 中分離鍵和值，並在反應中使用 useState 掛鈎將其存儲在數組中

Question

function Graph() {
  const [tcases, setCases] = useState([]);
  const [recovered, setRecovered] = useState([]);
  const [deaths, setDeaths] = useState([]);
  useEffect(() => {
    axios
      .get("https://disease.sh/v3/covid-19/historical/all?lastdays=all")
      .then((res) => {
        setCases(Object.values(res.data.cases));
        setRecovered(Object.values(res.data.recovered)));
        setDeaths(Object.values(res.data.deaths)));
      })
      .catch((err) => {
        console.log(err);
      });
  }, []);

我試過上面的代碼..它說病例、康復和死亡未定義

API 使用：點擊這里查看 api我想要這樣..請幫助:)

   tcases=[555,654,941...........]

   recovered=[17,18,26.........]

    deaths=[28,30,36...........]

謝謝！

Answer 1

function Graph() {
  const [tcases, setCases] = useState([]);
  const [recovered, setRecovered] = useState([]);
  const [deaths, setDeaths] = useState([]);
  const [date, setDate] = useState([]);
  useEffect(() => {
    axios
      .get("https://disease.sh/v3/covid-19/historical/all?lastdays=all")
      .then(res => {
        setCases(JSON.parse(JSON.stringify(Object.values(res.data.cases))));
        setDeaths(JSON.parse(JSON.stringify(Object.values(res.data.deaths))));
        setRecovered(JSON.parse(JSON.stringify(Object.values(res.data.recovered))));
        
      })
      .catch(err => {
        console.log(err);
      });
  }, []);

JSON.stringify 返回一個字符串。為了以數組格式存儲它，我們必須使用 JSON.parse 返回一個 object。