我正在尝试在删除后更新元素,而不刷新页面。目前,如果删除记录,需要刷新页面才能看到结果。据我所知,需要更新useState
,但我不知道该怎么做。如果我循环useEffect
,它会很慢,但我认为循环get
响应不是最好的主意。
- 从数据库中获取所有记录
const PostsGetUtill = () => {
const [posts, setPosts] = useState([]);
const fetchPosts = () => {
axios.get("api/v1.0/post/get").then(response => {
console.log(response.data);
setPosts(response.data);
}).catch(function (error) {
if (error.response) {
console.log(error.response.data);
console.log(error.response.status);
console.log(error.response.headers);
} else if (error.request) {
console.log(error.request);
} else {
console.log('Error', error.message);
}
console.log(error.config);
});
};
useEffect(() => {
fetchPosts();
}, []); // }, [fetchPosts]); <--- working well with loop
return (
<section className="container-post">
<PostMansonry posts={posts} columns={3} />
</section>
);
};
export default PostsGetUtill;
- 对记录进行排序和映射
export default function PostMansonry({ posts, columns }) {
return (
<section className="masonry" style={{ gridTemplateColumns: `repeat(${columns}, minmax(275px, 1fr))` }}>
{posts.sort((a, b) => a.zonedDateTime < b.zonedDateTime ? 1 : -1).map((posts, index) =>
<MasonryPost {...{ posts, index, key: index }} />)
}
</section>
)
}
- 将数据放入卡
export default function MasonryPost({ posts, index }) {
return (
<div key={index} className="masonry-post">
<div className="card">
<div className="card-body">
<h5 className="card-title">{posts.title}</h5>
<p className="card-text">{posts.description}</p>
<p className="card-text"><small className="text-muted"> {posts.zonedDateTime}</small></p>
<div><button type="button" onClick={(e) => PostsDeleteUtill(posts.post_Id)} className="btn btn-danger">Delete</button></div>
</div>
</div>
</div>
)
}
- 删除
const PostsDeleteUtill = async (post_Id) => {
axios.delete(`api/v1.0/post/delete/${post_Id}`).then(response => {
console.log(response);
}).catch((error) => {
if (error.response) {
console.log(error.response.data);
console.log(error.response.status);
console.log(error.response.headers);
} else if (error.request) {
console.log(error.request);
} else {
console.log('Error', error.message);
}
console.log('error config', error.config);
});
};
export default PostsDeleteUtill;
基本上,您需要做的是在PostsDeleteUtill
函数中,在axios.delete
的promise返回中,更新posts
状态,该状态在PostsGetUtill
中设置。
为了做到这一点,你有两个选项:
- 使用全局状态(React Context、Redux等(
- 将
setPosts
手柄一直传递到PostsDeleteUtill
我认为选项1对您的特定情况来说更干净一些,但如果您在项目中的其他地方不需要全局状态,那么也许可以使用一个不那么干净的解决方案,而不是只为一件事实现整个全局状态结构。
选项1伪代码:
您的PostsGetUtill
组件将使用全局状态而不是本地状态:
const PostsGetUtill = () => {
// Remove this:
// const [posts, setPosts] = useState([]);
const fetchPosts = () => {
axios.get("api/v1.0/post/get").then(response => {
console.log(response.data);
// Instead of a local "setPosts" you would have a global
// "setPosts" (in Redux, this would be a dispatch)
dispatch({type: "PUT_POSTS", action: response.data})
}).catch(function (error) {
// No changes here...
});
};
// This runs only the first time you load this component
useEffect(() => {
fetchPosts();
}, []);
// Use your global state here as well:
return (
<section className="container-post">
<PostMansonry posts={globalState.posts} columns={3} />
</section>
);
};
export default PostsGetUtill;
在您的PostsDeleteUtill
功能中:
const PostsDeleteUtill = async (post_Id) => {
axios.delete(`api/v1.0/post/delete/${post_Id}`).then(response => {
// Update global state here. Probably filter the data to remove
// the deleted record
const updatedPosts = globalState.posts.filter(post => post.id !== response.data.id)
}).catch((error) => {
// No changes here
});
};
export default PostsDeleteUtill;
选项2伪代码:
在PostsGetUtill
组件中,创建并传递handleRemovePost
:
// Your existing code ...
const handleRemovePost = (postID) => {
const filteredPosts = posts.filter(post => post.id !=== postID)
setPosts(filteredPosts)
}
return (
<section className="container-post">
<PostMansonry posts={posts} columns={3} handleRemovePost={handleRemovePost} />
</section>
);
在PostMansonry
中,再次传递您的handleRemovePost
export default function PostMansonry({ posts, columns, handleRemovePost }) {
return (
// Your existing code ...
<MasonryPost {...{ posts, index, key: index, handleRemovePost }} />)
)
}
再次在您的MasonryPost
中
export default function MasonryPost({ posts, index, handleRemovePost }) {
return (
// Your existing code ...
<button type="button" onClick={(e) => PostsDeleteUtill(posts.post_Id, handleRemovePost)} className="btn btn-danger">Delete</button>
)
}
最后:
const PostsDeleteUtill = async (post_Id, handleRemovePost) => {
axios.delete(`api/v1.0/post/delete/${post_Id}`).then(response => {
handleRemovePost(response);
})
};
PS:请注意,我只添加了一个伪代码作为参考,试图指出代码中需要更新的特定部分。如果你需要更多关于全局状态的信息,你可以查看React Context和Redux