React useActionState 中间件管道：构建强大的操作处理链

            // Middleware function
const loggerMiddleware = (action, setState) => {
 console.log('Action:', action);
 setState(action);
};

// Custom useActionState hook
const useActionStateWithMiddleware = (initialState, middleware) => {
 const [state, setState] = React.useState(initialState);

 const dispatch = React.useCallback(
 action => {
 middleware(action, setState);
 },
 [middleware, setState]
 );

 return [state, dispatch];
};

// Usage
const MyComponent = () => {
 const [count, setCount] = useActionStateWithMiddleware(0, loggerMiddleware);

 const increment = () => {
 setCount(count + 1);
 };

 return (
 

 
Count: {count}
 Increment
 
 );
};
            

              
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            const applyMiddleware = (...middlewares) => (action, setState) => {
 middlewares.forEach(middleware => {
 action = middleware(action, setState) || action; // Allow middleware to modify/replace the action.
 });
 setState(action);  // This line will always execute and set the final state.
};

            

              
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            // Middleware functions
const loggerMiddleware = (action) => {
 console.log('Action:', action);
 return action;
};

const uppercaseMiddleware = (action) => {
 if (typeof action === 'string') {
 return action.toUpperCase();
 }
 return action;
};

const asyncMiddleware = (action, setState) => {
 if (typeof action === 'function') {
 action((newAction) => setState(newAction));
 return;
 }
 return action;
};

const myMiddleware = (action, setState) => {
 if (action.type === "API_CALL") {
 setTimeout(() => {
 setState(action.payload)
 }, 1000)
 return; //Prevent immediate state change
 }
 return action;
}

// Custom useActionState hook
const useActionStateWithMiddleware = (initialState, ...middlewares) => {
 const [state, setState] = React.useState(initialState);

 const dispatch = React.useCallback(
 action => {
 applyMiddleware(...middlewares)(action, setState);
 },
 [setState, ...middlewares]
 );

 return [state, dispatch];
};

// Usage
const MyComponent = () => {
 const [message, setMessage] = useActionStateWithMiddleware('', loggerMiddleware, uppercaseMiddleware, asyncMiddleware, myMiddleware);

 const updateMessage = (newMessage) => {
 setMessage(newMessage);
 };

 const asyncUpdate = (payload) => (setState) => {
 setTimeout(() => {
 setState(payload);
 }, 2000);
 };

 const apiCall = (payload) => {
 setMessage({type: "API_CALL", payload: payload})
 }

 return (
 

 
Message: {message}
  updateMessage('hello world')}>Update Message
  setMessage(asyncUpdate('Async Hello'))}>Async Update
  apiCall('Api Data')}>API CALL
 
 );
};
            

              
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            const errorHandlingMiddleware = (action, setState) => {
 try {
 setState(action);
 } catch (error) {
 console.error('Error:', error);
 // Log the error to a service like Sentry or Rollbar
 }
};

            

              
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            const conditionalMiddleware = (condition, middleware) => (action, setState) => {
 if (condition(action)) {
 middleware(action, setState);
 } else {
 setState(action);
 }
};

// Usage
const useActionStateWithConditionalMiddleware = (initialState, middleware, condition) => {
 const [state, setState] = React.useState(initialState);

 const dispatch = React.useCallback(
 action => {
 if (condition(action)) {
 middleware(action, setState);
 } else {
 setState(action);
 }
 },
 [middleware, setState, condition]
 );

 return [state, dispatch];
};

const MyComponent = () => {
 const [count, setCount] = useActionStateWithConditionalMiddleware(0, loggerMiddleware, (action) => typeof action === 'number');

 const increment = () => {
 setCount(count + 1);
 };

 const updateMessage = (message) => {
 setCount(message);
 };

 return (
 

 
Count: {count}
 Increment
  updateMessage('Not a number')}>Update Message
 
 );
};
            

              
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            const apiMiddleware = (action, setState) => {
 if (typeof action === 'function') {
 action(setState);
 } else {
 setState(action);
 }
};

// Usage
const MyComponent = () => {
 const [data, setData] = useActionStateWithMiddleware(null, apiMiddleware);

 const fetchData = () => (setState) => {
 fetch('https://api.example.com/data')
 .then(response => response.json())
 .then(data => setState(data));
 };

 const handleClick = () => {
 setData(fetchData());
 };

 return (
 

 Fetch Data
 {data && 
{JSON.stringify(data, null, 2)}
}
 
 );
};
            

              
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            const authMiddleware = (action, setState) => {
 if (action.type === 'PROTECTED_ACTION' && !isAuthenticated()) {
 redirectToLoginPage();
 } else {
 setState(action);
 }
};

            

              
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            const validationMiddleware = (action, setState) => {
 if (action.type === 'FORM_SUBMIT') {
 const errors = validateForm(action.payload);
 if (errors.length > 0) {
 displayErrorMessages(errors);
 } else {
 setState(action.payload);
 }
 } else {
 setState(action);
 }
};

            

              
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            const analyticsMiddleware = (action, setState) => {
 trackEvent(action.type, action.payload);
 setState(action);
};

function trackEvent(eventType, eventData) {
 // Replace with your analytics tracking code
 console.log(`Tracking event: ${eventType} with data:`, eventData);
}

            

              
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