javascript - useEffect 中的 setState 循环应用程序

Question

为什么会出现无限循环错误？React 指的是标有 的行*：

function Blog() {
    const [blog, setBlog] = useState({});
    const query = useQuery();

    async function takeBlog(query) {
        const _data = await (await fetch(`${root}/api/blog/${query}`)).json();
        console.log(_data.blog)
        setBlog(_.get(_data, 'blog', {}));  // *
    }

    useEffect(() => {
        takeBlog(query);
    }, []);

    return (
        <div className="blog_page">
            <div className="container">
                <div className="top">
                </div>
                <div className="other ab">
                    <div className="left">
                        <Navbar active='blogs' />
                    </div>
                    <div className="right">
                        <Posts posts={_.get(blog, 'articles', [])} />
                    </div>
                </div>
            </div>
        </div>
    );
}

export default Blog;

标签： javascriptreactjslodash

Answer 1

给你一个解决方案

function Blog() {
    const [blog, setBlog] = useState({});
    const query = useQuery();

    async function takeBlog(query) {
        const _data = await (await fetch(`${root}/api/blog/${query}`)).json();
        console.log(_data.blog)
        setBlog(_.get(_data, 'blog', {}));  // *
    }

    useEffect(() => {
      const keys = Object.keys(blog);
      if (!keys.length) {
        takeBlog(query);
      }
    }, []);

    return (
        <div className="blog_page">
            <div className="container">
                <div className="top">
                </div>
                <div className="other ab">
                    <div className="left">
                        <Navbar active='blogs' />
                    </div>
                    <div className="right">
                        <Posts posts={_.get(blog, 'articles', [])} />
                    </div>
                </div>
            </div>
        </div>
    );
}

export default Blog;

检查 useEffect 中的博客状态变量作为条件