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条件语句在 useEffect 中不起作用

[英]Conditional statement not working in useEffect

It seems that the conditional statement does not apply properly within useEffect.似乎条件语句在 useEffect 中不能正确应用。 'UserPortInfo' is 1, but why 'templateCss' is applied as 'first-theme'? 'UserPortInfo' 为 1,但为什么将 'templateCss' 应用为 'first-theme'? And why does the console work several times?为什么控制台可以工作多次?

  // portfolio info get
  const [userPortInfo, setUserPortInfo] = useState('');

  const getPortInfo = () => {
    axios
      .get(`http://localhost:3001/portfolios`, {
        headers: {
          Authorization: `Bearer ${getToken}`,
        },
      })
      .then((res) => {
        const datas = res.data.data;
        datas.forEach((e) => {
          if (e.portfolio_idx === Number(portfolio_idx)) {
            setUserPortInfo(e.template);
          }
        });
      })
      .catch((err) => console.log(err));
  };

const [templateCss, setTemplateCss] = useState('');

  useEffect(() => {
    getUserInfo();
    getPortfolio();
    getPortInfo();
    userPortInfo == 1
      ? setTemplateCss('second-theme')
      : setTemplateCss('first-theme');
  }, []);

  console.log(userPortInfo);
  console.log(templateCss);

在此处输入图像描述

The problem is that you read userPortInfo exactly once and before your async call completes.问题是您在异步调用完成之前只读取了一次 userPortInfo。

  useEffect(() => {
    getUserInfo();
    getPortfolio();
    getPortInfo();
    userPortInfo == 1
      ? setTemplateCss('second-theme')
      : setTemplateCss('first-theme');
  }, []); <---- empty array means it is only run once

Maybe instead move it to another effect?也许改为将其移至另一种效果?

  useEffect(() => {
    getUserInfo();
    getPortfolio();
    getPortInfo();
  }, [])

useEffect(() => {
  userPortInfo == 1
      ? setTemplateCss('second-theme')
      : setTemplateCss('first-theme');
  }, []);
}, [userPortInfo] ) 

This means that when userPortInfo changes your css is updated这意味着当 userPortInfo 更改时,您的 css 会更新

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