開源日報每天推薦一個 GitHub 優質開源項目和一篇精選英文科技或編程文章原文,堅持閱讀《開源日報》,保持每日學習的好習慣。
2024年1月28日,開源日報第1088期:
今日推薦開源項目:《drawio-desktop》
今日推薦英文原文:《A Super Simple Guide to the Render Props Pattern in React》
開源項目
今日推薦開源項目:《drawio-desktop》傳送門:項目鏈接
推薦理由: drawio-desktop是一個基於Electron的圖表和白板桌面應用程序,它包裝了核心的draw.io編輯器
網站直達:www.diagrams.net
英文原文
今日推薦英文原文:A Super Simple Guide to the Render Props Pattern in React
推薦理由:渲染屬性模式是React中一種優雅的模式,用於在組件間以清晰可重用的方式共享數據或功能,創建渲染屬性組件如DateProvider
,通過渲染傳遞的函數提供數據,提高復用性
A Super Simple Guide to the Render Props Pattern in React
Render Props Pattern in React
Hey there, React enthusiasts! Today, we』re diving into an elegant and versatile pattern in React: the Render Props pattern. This pattern allows you to share data or functionality between components in a clean and reusable way, and it』s simpler than you might think.
What』s the Render Props Pattern?
Imagine you』re sharing your favorite book with a friend. You don』t just give them the book; you read it together, enjoying each page. The Render Props pattern is like that shared reading experience. It』s a way to share data or functionality by rendering a function as a child component. This function receives data as an argument and returns what to render based on that data.
When Do We Use the Render Props Pattern in React?
The Render Props pattern is handy when you want to share data or functionality between components, especially in situations where you need to customize the rendering based on that data. It』s a versatile approach for making your React components more reusable.
Creating a Render Props Component
Let』s create a simple Render Props component that shares the current date:
import React from 'react';
class DateProvider extends React.Component {
render() {
const currentDate = new Date();
return this.props.children(currentDate);
}
}
export default DateProvider;
In this example, DateProvider
is our Render Props component. It provides the current date by rendering the function passed as children
and passing the currentDate
as an argument.
Using the Render Props Component
Now, let』s see how we can use the DateProvider
to display the current date in our app:
import React from 'react';
import DateProvider from './DateProvider';
class App extends React.Component {
render() {
return (
<div className="App">
<h1>Welcome to My React App</h1>
<DateProvider>
{(currentDate) => (
<p>Today's date is: {currentDate.toDateString()}</p>
)}
</DateProvider>
</div>
);
}
}
export default App;
In this example:
- We import the
DateProvider
component. - Inside the
App
component, we wrap the content we want to share the current date with inside the<DateProvider>
component. - We render a function as a child, which receives the
currentDate
as an argument and returns what to render. In this case, we display the current date.
Real-World Example: Token Validation
Now, let』s take the Render Props pattern to the real world. Imagine you have a React app that requires user authentication. You want to validate user data stored localStorage
against an API. If successful, you'd like to pass the user's ID to child components or display an error message if the validation fails.
Here』s how you can modify your AzureProvider
component to use the Render Props pattern:
import React, { useEffect, useState } from 'react';
const AzureProvider = (props) => {
const [error, setError] = useState(null);
const [globalProvider, setGlobalProvider] = useState(null);
const validate = async () => {
let provider;
try {
const token = localStorage.getItem('userToken');
if (!token) {
throw new Error('No user token found in localStorage');
}
// Make an API call to validate the token
const response = await fetch('https://your-api-endpoint.com/validate', {
method: 'POST',
headers: {
'Authorization': `Bearer ${token}`,
},
});
if (!response.ok) {
throw new Error('Token validation failed');
}
// Assuming the response contains user information with an 'id' field
const userData = await response.json();
provider = userData.id;
} catch (error) {
console.error(error);
setError('Token validation failed. Please log in again.');
} finally {
if (provider) {
setGlobalProvider(provider);
}
}
};
useEffect(() => {
validate();
}, []);
return props.children(globalProvider, error);
};
export default AzureProvider;
In this modified AzureProvider
component:
- We use
async/await
it to perform token validation. - We check for a token
localStorage
and handle validation errors. - We set the
provider
anderror
states as appropriate. - We passed both
provider
anderror
values to the children viaprops.children
.
Now, you can use the AzureProvider
as shown in your App
component:
import React from 'react';
import AzureProvider from './AzureProvider';
class App extends React.Component {
render() {
return (
<div className="App">
<h1>Welcome to My React App</h1>
<AzureProvider>
{(provider, error) => {
if (error) {
return <p style={{ color: "red" }}>{error}</p>;
}
if (provider) {
return <Component provider={provider} />; // Replace 'Component' with the actual name of your child component
}
return <p>Loading</p>;
}}
</AzureProvider>
</div>
);
}
}
export default App;
Here, we render a function as a child within the AzureProvider
, which receives both the provider
and error
values and decides what to render based on the outcome of the token validation.
The Render Props pattern is a powerful tool for sharing data and functionality in your React components, making your code cleaner, more reusable, and more adaptable. So, whether you』re displaying the current date or managing user authentication, Render Props is your go-to pattern in the React kitchen.
Conclusion
In this guide, we』ve explored the Render Props pattern in React, a flexible and powerful approach to sharing data and functionality between components. We began with a simple example of displaying the current date and extended it to a real-world scenario of user token validation. With Render Props, you can create more organized, reusable, and efficient components in your React applications.
When to Use the Render Props Pattern:
- Customization: Use Render Props when you need to customize the rendering of a component based on some data or functionality.
- Data Sharing: It』s ideal for sharing data or behavior between components in a clean and maintainable way.
- Reusability: Employ Render Props to make your components more reusable, as they can adapt to different use cases.
- Flexibility: Choose this pattern when you want a flexible and versatile method for component composition.
When to Avoid the Render Props Pattern:
- Simplicity: If your data-sharing needs are straightforward, and you don』t require customization, using the Render Props pattern might add unnecessary complexity to your code.
- Overuse: Avoid overusing Render Props in situations where simpler solutions like prop drilling or context API suffice.
- Nesting Complexity: Be cautious when nesting multiple components with Render Props, as it can make your code harder to maintain and understand.
In essence, the Render Props pattern is a fantastic tool for enhancing the reusability and flexibility of your React components. However, like any tool, it should be used judiciously, considering the complexity and requirements of your specific project. So, keep it in your toolkit and apply it where it fits best, ensuring a seamless and efficient development experience in your React applications.
Happy coding, and keep React-ing in style! 🚀💻
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