跳至主要内容

前端開發實戰

今天用Claude Code從零開始構建一個電商產品展示平臺。這個專案會涵蓋前端開發的核心要素:響應式UI、狀態管理、元件庫、效能最佳化。

專案概述​

要做什麼​

做一個電商產品展示平臺,包括:

  • 響應式UI,適配各種裝置
  • 全域性狀態管理(Context + Hooks)
  • 可複用元件庫
  • 效能最佳化(程式碼分割、懶載入)
  • 動畫和互動體驗
  • 打包最佳化

技術棧​

  • 框架: React 18 + React Router v6
  • 狀態管理: React Context API + 自定義Hooks
  • 樣式方案: CSS Modules + Styled Components
  • 構建工具: Vite(替代Create React App)
  • UI元件: 自建元件庫 + Headless UI
  • 動畫: Framer Motion
  • 表單: React Hook Form + Zod驗證
  • 工具: Claude Code作為主要開發工具

需要多久​

  • 傳統開發: 3-5天
  • 用Claude Code: 3-5小時
  • 效率提升: 8-10倍

準備工作​

環境要求​

# 检查Node.js版本(需要18+)
node --version

# 检查npm版本
npm --version

# 检查Git版本
git --version

建立專案​

# 使用Vite创建React项目
npm create vite@latest ecommerce-frontend -- --template react

# 进入项目目录
cd ecommerce-frontend

# 初始化Git仓库
git init
git branch -M main

# 安装依赖
npm install

啟動Claude Code​

# 在项目目录启动Claude Code
claude

第一階段：專案架構設計​

第一輪對話​

我要创建一个电商产品展示平台:

1. 产品列表页(过滤、搜索、排序)
2. 产品详情页
3. 购物车
4. 收藏功能
5. 响应式设计
6. 性能优化

技术栈:
- React 18 + Vite
- React Router v6
- 自定义状态管理(Context + Hooks)
- CSS Modules + Tailwind CSS

帮我设计项目结构并创建基础文件。

Claude Code會建立完整的專案結構:

📁 创建项目结构...

✓ 创建 src/components/common/
✓ 创建 src/components/pages/
✓ 创建 src/context/
✓ 创建 src/hooks/
✓ 创建 src/services/
✓ 创建 src/utils/
✓ 创建 src/styles/
✓ 创建 src/assets/
✓ 更新路由配置

專案結構​

ecommerce-frontend/
├── src/
│   ├── components/
│   │   ├── common/
│   │   │   ├── Button/
│   │   │   ├── Card/
│   │   │   ├── Modal/
│   │   │   ├── Input/
│   │   │   ├── Select/
│   │   │   └── LoadingSpinner/
│   │   ├── layout/
│   │   │   ├── Header/
│   │   │   ├── Footer/
│   │   │   ├── Sidebar/
│   │   │   └── Navigation/
│   │   └── features/
│   │       ├── ProductCard/
│   │       ├── ProductList/
│   │       ├── ProductFilter/
│   │       ├── ShoppingCart/
│   │       └── Wishlist/
│   ├── pages/
│   │   ├── Home/
│   │   ├── Products/
│   │   ├── ProductDetail/
│   │   ├── Cart/
│   │   ├── Wishlist/
│   │   └── NotFound/
│   ├── context/
│   │   ├── AuthContext.js
│   │   ├── CartContext.js
│   │   ├── WishlistContext.js
│   │   └── ThemeContext.js
│   ├── hooks/
│   │   ├── useCart.js
│   │   ├── useWishlist.js
│   │   ├── useLocalStorage.js
│   │   ├── useDebounce.js
│   │   └── useIntersectionObserver.js
│   ├── services/
│   │   ├── api.js
│   │   ├── productService.js
│   │   └── analytics.js
│   ├── utils/
│   │   ├── format.js
│   │   ├── validation.js
│   │   └── constants.js
│   ├── styles/
│   │   ├── global.css
│   │   ├── variables.css
│   │   └── animations.css
│   ├── App.jsx
│   └── main.jsx
├── public/
│   └── favicon.svg
├── index.html
├── vite.config.js
├── tailwind.config.js
└── package.json

第二階段：UI元件開發​

建立基礎元件庫​

先创建可复用的基础组件:
1. Button组件(多种样式和尺寸)
2. Card组件
3. Input组件
4. Modal组件
5. LoadingSpinner组件

每个组件都要支持主题切换。

Button元件​

src/components/common/Button/Button.jsx:

import React from 'react';
import styles from './Button.module.css';

const Button = ({
  children,
  variant = 'primary',
  size = 'medium',
  disabled = false,
  loading = false,
  fullWidth = false,
  icon,
  onClick,
  type = 'button',
  className = '',
  ...props
}) => {
  const buttonClasses = [
    styles.button,
    styles[variant],
    styles[size],
    fullWidth && styles.fullWidth,
    disabled && styles.disabled,
    loading && styles.loading,
    className,
  ]
    .filter(Boolean)
    .join(' ');

  return (
    <button
      type={type}
      className={buttonClasses}
      onClick={onClick}
      disabled={disabled || loading}
      {...props}
    >
      {loading && <span className={styles.spinner} />}
      {icon && !loading && <span className={styles.icon}>{icon}</span>}
      <span className={styles.content}>{children}</span>
    </button>
  );
};

export default Button;

src/components/common/Button/Button.module.css:

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  border: none;
  border-radius: 0.5rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  position: relative;
  overflow: hidden;
}

.button:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* Variants */
.primary {
  background: var(--primary-color);
  color: white;
}

.primary:hover:not(:disabled) {
  background: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
}

.secondary {
  background: white;
  color: var(--text-primary);
  border: 2px solid var(--border-color);
}

.secondary:hover:not(:disabled) {
  border-color: var(--primary-color);
  color: var(--primary-color);
}

.outline {
  background: transparent;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

.outline:hover:not(:disabled) {
  background: var(--primary-color);
  color: white;
}

.ghost {
  background: transparent;
  color: var(--text-secondary);
}

.ghost:hover:not(:disabled) {
  background: var(--bg-gray);
  color: var(--text-primary);
}

.danger {
  background: var(--danger-color);
  color: white;
}

.danger:hover:not(:disabled) {
  background: #dc2626;
  box-shadow: 0 4px 12px rgba(239, 68, 68, 0.4);
}

/* Sizes */
.small {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.medium {
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
}

.large {
  padding: 1rem 2rem;
  font-size: 1.125rem;
}

/* States */
.disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.loading {
  pointer-events: none;
}

.fullWidth {
  width: 100%;
}

.spinner {
  width: 1rem;
  height: 1rem;
  border: 2px solid transparent;
  border-top-color: currentColor;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

.icon {
  display: inline-flex;
  align-items: center;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* 响应式设计 */
@media (max-width: 768px) {
  .medium {
    padding: 0.625rem 1.25rem;
    font-size: 0.9375rem;
  }

  .large {
    padding: 0.875rem 1.75rem;
    font-size: 1rem;
  }
}

Card元件​

src/components/common/Card/Card.jsx:

import React from 'react';
import styles from './Card.module.css';

const Card = ({
  children,
  variant = 'default',
  hoverable = false,
  padding = 'medium',
  shadow = 'medium',
  className = '',
  onClick,
  ...props
}) => {
  const cardClasses = [
    styles.card,
    styles[variant],
    styles[padding],
    styles[shadow],
    hoverable && styles.hoverable,
    onClick && styles.clickable,
    className,
  ]
    .filter(Boolean)
    .join(' ');

  return (
    <div
      className={cardClasses}
      onClick={onClick}
      role={onClick ? 'button' : undefined}
      tabIndex={onClick ? 0 : undefined}
      {...props}
    >
      {children}
    </div>
  );
};

export default Card;

src/components/common/Card/Card.module.css:

.card {
  background: white;
  border-radius: 1rem;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

/* Variants */
.default {
  border: 1px solid var(--border-color);
}

.bordered {
  border: 2px solid var(--border-color);
}

.elevated {
  border: none;
}

/* Padding */
.small {
  padding: 1rem;
}

.medium {
  padding: 1.5rem;
}

.large {
  padding: 2rem;
}

/* Shadow */
.none {
  box-shadow: none;
}

.small {
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.medium {
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1),
              0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

.large {
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1),
              0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

/* Hover effect */
.hoverable:hover {
  transform: translateY(-4px);
}

.hoverable.medium:hover {
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1),
              0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

.clickable {
  cursor: pointer;
}

.clickable:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* 响应式 */
@media (max-width: 768px) {
  .medium {
    padding: 1rem;
  }

  .large {
    padding: 1.5rem;
  }
}

Modal元件​

src/components/common/Modal/Modal.jsx:

import React, { useEffect, useRef } from 'react';
import { createPortal } from 'react-dom';
import styles from './Modal.module.css';

const Modal = ({
  isOpen = false,
  onClose,
  title,
  children,
  size = 'medium',
  closeOnOverlayClick = true,
  closeOnEscape = true,
  showCloseButton = true,
  className = '',
}) => {
  const modalRef = useRef(null);
  const previousActiveElement = useRef(null);

  useEffect(() => {
    if (isOpen) {
      // 保存当前聚焦元素
      previousActiveElement.current = document.activeElement;

      // 禁用背景滚动
      document.body.style.overflow = 'hidden';

      // 聚焦到modal
      modalRef.current?.focus();

      // 监听ESC键
      if (closeOnEscape) {
        const handleEscape = (e) => {
          if (e.key === 'Escape') {
            onClose();
          }
        };
        document.addEventListener('keydown', handleEscape);
        return () => document.removeEventListener('keydown', handleEscape);
      }
    } else {
      // 恢复背景滚动
      document.body.style.overflow = '';

      // 恢复焦点
      previousActiveElement.current?.focus();
    }
  }, [isOpen, closeOnEscape, onClose]);

  if (!isOpen) return null;

  const handleOverlayClick = (e) => {
    if (closeOnOverlayClick && e.target === e.currentTarget) {
      onClose();
    }
  };

  const modalContent = (
    <div
      className={styles.overlay}
      onClick={handleOverlayClick}
      aria-modal="true"
      role="dialog"
      aria-labelledby={title ? 'modal-title' : undefined}
    >
      <div
        ref={modalRef}
        className={`${styles.modal} ${styles[size]} ${className}`}
        tabIndex={-1}
      >
        {(title || showCloseButton) && (
          <div className={styles.header}>
            {title && <h2 id="modal-title" className={styles.title}>{title}</h2>}
            {showCloseButton && (
              <button
                onClick={onClose}
                className={styles.closeButton}
                aria-label="关闭"
              >
                ✕
              </button>
            )}
          </div>
        )}
        <div className={styles.content}>
          {children}
        </div>
      </div>
    </div>
  );

  return createPortal(modalContent, document.body);
};

export default Modal;

src/components/common/Modal/Modal.module.css:

.overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 1rem;
  backdrop-filter: blur(4px);
  animation: fadeIn 0.2s ease;
}

.modal {
  background: white;
  border-radius: 1rem;
  max-height: 90vh;
  display: flex;
  flex-direction: column;
  animation: slideUp 0.3s ease;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
}

/* Sizes */
.small {
  width: 100%;
  max-width: 400px;
}

.medium {
  width: 100%;
  max-width: 600px;
}

.large {
  width: 100%;
  max-width: 800px;
}

.fullscreen {
  width: 100%;
  height: 100%;
  max-width: none;
  max-height: 100%;
  border-radius: 0;
}

.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  margin: 0;
}

.closeButton {
  background: transparent;
  border: none;
  font-size: 1.5rem;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 0.25rem;
  line-height: 1;
  border-radius: 0.375rem;
  transition: all 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.closeButton:hover {
  background: var(--bg-gray);
  color: var(--text-primary);
}

.content {
  padding: 1.5rem;
  overflow-y: auto;
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.95);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* 响应式 */
@media (max-width: 768px) {
  .overlay {
    padding: 0.5rem;
  }

  .header,
  .content {
    padding: 1rem;
  }

  .small,
  .medium,
  .large {
    max-width: 100%;
  }
}

Input元件​

src/components/common/Input/Input.jsx:

import React, { forwardRef } from 'react';
import styles from './Input.module.css';

const Input = forwardRef((
  {
    label,
    error,
    icon,
    helperText,
    fullWidth = false,
    variant = 'outlined',
    size = 'medium',
    className = '',
    ...props
  },
  ref
) => {
  const inputClasses = [
    styles.input,
    styles[variant],
    styles[size],
    error && styles.error,
    icon && styles.withIcon,
    fullWidth && styles.fullWidth,
    className,
  ]
    .filter(Boolean)
    .join(' ');

  const wrapperClasses = [
    styles.wrapper,
    fullWidth && styles.fullWidth,
  ]
    .filter(Boolean)
    .join(' ');

  return (
    <div className={wrapperClasses}>
      {label && <label className={styles.label}>{label}</label>}
      <div className={styles.inputContainer}>
        {icon && <span className={styles.icon}>{icon}</span>}
        <input
          ref={ref}
          className={inputClasses}
          {...props}
        />
      </div>
      {error && <span className={styles.errorText}>{error}</span>}
      {helperText && !error && (
        <span className={styles.helperText}>{helperText}</span>
      )}
    </div>
  );
});

Input.displayName = 'Input';

export default Input;

src/components/common/Input/Input.module.css:

.wrapper {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.fullWidth {
  width: 100%;
}

.label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-primary);
}

.inputContainer {
  position: relative;
  display: flex;
  align-items: center;
}

.input {
  width: 100%;
  border: 1px solid var(--border-color);
  border-radius: 0.5rem;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  color: var(--text-primary);
  background: white;
  transition: all 0.2s ease;
}

.input::placeholder {
  color: var(--text-placeholder);
}

.input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

/* Variants */
.outlined {
  background: white;
}

.filled {
  background: var(--bg-gray);
  border-color: transparent;
}

.filled:focus {
  background: white;
  border-color: var(--primary-color);
}

.underlined {
  border: none;
  border-bottom: 2px solid var(--border-color);
  border-radius: 0;
  padding-left: 0;
  padding-right: 0;
}

.underlined:focus {
  border-color: var(--primary-color);
  box-shadow: none;
}

/* Sizes */
.small {
  padding: 0.5rem 0.75rem;
  font-size: 0.875rem;
}

.medium {
  padding: 0.75rem 1rem;
  font-size: 1rem;
}

.large {
  padding: 1rem 1.25rem;
  font-size: 1.125rem;
}

/* States */
.error {
  border-color: var(--danger-color);
}

.error:focus {
  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1);
}

.withIcon {
  padding-left: 2.5rem;
}

.icon {
  position: absolute;
  left: 0.75rem;
  color: var(--text-secondary);
  pointer-events: none;
}

.errorText {
  font-size: 0.75rem;
  color: var(--danger-color);
}

.helperText {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

/* 响应式 */
@media (max-width: 768px) {
  .medium {
    padding: 0.625rem 0.875rem;
  }

  .large {
    padding: 0.875rem 1.125rem;
    font-size: 1rem;
  }
}

第三階段：全域性狀態管理​

建立Context系統​

你: 创建一个基于React Context的状态管理系统,包括:
1. 购物车状态(CartContext)
2. 收藏夹状态(WishlistContext)
3. 认证状态(AuthContext)
4. 主题状态(ThemeContext)

每个Context都要提供对应的自定义Hook,并实现持久化存储。

CartContext​

src/context/CartContext.jsx:

import React, { createContext, useContext, useReducer, useEffect } from 'react';
import { loadFromLocalStorage, saveToLocalStorage } from '../utils/storage';

const CartContext = createContext();

const CART_STORAGE_KEY = 'shopping_cart';

// 初始状态
const initialState = {
  items: [],
  totalItems: 0,
  totalPrice: 0,
  isLoading: false,
  error: null,
};

// Reducer
function cartReducer(state, action) {
  switch (action.type) {
    case 'CART_LOAD_START':
      return {
        ...state,
        isLoading: true,
        error: null,
      };

    case 'CART_LOAD_SUCCESS':
      return {
        ...state,
        isLoading: false,
        ...action.payload,
      };

    case 'CART_LOAD_ERROR':
      return {
        ...state,
        isLoading: false,
        error: action.payload,
      };

    case 'CART_ADD_ITEM': {
      const existingItemIndex = state.items.findIndex(
        (item) => item.id === action.payload.id
      );

      let newItems;

      if (existingItemIndex > -1) {
        // Item already exists, update quantity
        newItems = state.items.map((item, index) =>
          index === existingItemIndex
            ? { ...item, quantity: item.quantity + action.payload.quantity }
            : item
        );
      } else {
        // Add new item
        newItems = [...state.items, { ...action.payload }];
      }

      const totals = calculateTotals(newItems);

      return {
        ...state,
        items: newItems,
        ...totals,
      };
    }

    case 'CART_REMOVE_ITEM': {
      const newItems = state.items.filter((item) => item.id !== action.payload);
      const totals = calculateTotals(newItems);

      return {
        ...state,
        items: newItems,
        ...totals,
      };
    }

    case 'CART_UPDATE_QUANTITY': {
      const newItems = state.items.map((item) =>
        item.id === action.payload.id
          ? { ...item, quantity: action.payload.quantity }
          : item
      );

      const totals = calculateTotals(newItems);

      return {
        ...state,
        items: newItems,
        ...totals,
      };
    }

    case 'CART_CLEAR':
      return {
        ...state,
        items: [],
        totalItems: 0,
        totalPrice: 0,
      };

    case 'CART_SET_ITEMS': {
      const totals = calculateTotals(action.payload);
      return {
        ...state,
        items: action.payload,
        ...totals,
      };
    };

    default:
      return state;
  }
}

// 计算总数和总价
function calculateTotals(items) {
  const totalItems = items.reduce((sum, item) => sum + item.quantity, 0);
  const totalPrice = items.reduce(
    (sum, item) => sum + item.price * item.quantity,
    0
  );

  return {
    totalItems,
    totalPrice: parseFloat(totalPrice.toFixed(2)),
  };
}

// Provider组件
export const CartProvider = ({ children }) => {
  const [state, dispatch] = useReducer(cartReducer, initialState);

  // 从本地存储加载购物车
  useEffect(() => {
    const loadCart = () => {
      dispatch({ type: 'CART_LOAD_START' });

      try {
        const savedCart = loadFromLocalStorage(CART_STORAGE_KEY);
        if (savedCart) {
          dispatch({
            type: 'CART_LOAD_SUCCESS',
            payload: savedCart,
          });
        } else {
          dispatch({ type: 'CART_LOAD_SUCCESS', payload: initialState });
        }
      } catch (error) {
        dispatch({
          type: 'CART_LOAD_ERROR',
          payload: '加载购物车失败',
        });
      }
    };

    loadCart();
  }, []);

  // 保存购物车到本地存储
  useEffect(() => {
    if (!state.isLoading) {
      saveToLocalStorage(CART_STORAGE_KEY, {
        items: state.items,
        totalItems: state.totalItems,
        totalPrice: state.totalPrice,
      });
    }
  }, [state.items, state.isLoading]);

  // Actions
  const addToCart = (product, quantity = 1) => {
    dispatch({
      type: 'CART_ADD_ITEM',
      payload: {
        id: product.id,
        name: product.name,
        price: product.price,
        image: product.image,
        quantity,
        addedAt: new Date().toISOString(),
      },
    });
  };

  const removeFromCart = (productId) => {
    dispatch({
      type: 'CART_REMOVE_ITEM',
      payload: productId,
    });
  };

  const updateQuantity = (productId, quantity) => {
    if (quantity <= 0) {
      removeFromCart(productId);
    } else {
      dispatch({
        type: 'CART_UPDATE_QUANTITY',
        payload: { id: productId, quantity },
      });
    }
  };

  const clearCart = () => {
    dispatch({ type: 'CART_CLEAR' });
  };

  const isInCart = (productId) => {
    return state.items.some((item) => item.id === productId);
  };

  const getItemQuantity = (productId) => {
    const item = state.items.find((item) => item.id === productId);
    return item ? item.quantity : 0;
  };

  const value = {
    ...state,
    addToCart,
    removeFromCart,
    updateQuantity,
    clearCart,
    isInCart,
    getItemQuantity,
  };

  return <CartContext.Provider value={value}>{children}</CartContext.Provider>;
};

// 自定义Hook
export const useCart = () => {
  const context = useContext(CartContext);

  if (!context) {
    throw new Error('useCart must be used within CartProvider');
  }

  return context;
};

WishlistContext​

src/context/WishlistContext.jsx:

import React, { createContext, useContext, useState, useEffect } from 'react';
import { loadFromLocalStorage, saveToLocalStorage } from '../utils/storage';

const WishlistContext = createContext();

const WISHLIST_STORAGE_KEY = 'user_wishlist';

export const WishlistProvider = ({ children }) => {
  const [items, setItems] = useState([]);
  const [isLoading, setIsLoading] = useState(true);

  // 加载收藏夹
  useEffect(() => {
    const loadWishlist = () => {
      try {
        const savedWishlist = loadFromLocalStorage(WISHLIST_STORAGE_KEY);
        setItems(savedWishlist || []);
      } catch (error) {
        console.error('加载收藏夹失败:', error);
      } finally {
        setIsLoading(false);
      }
    };

    loadWishlist();
  }, []);

  // 保存收藏夹
  useEffect(() => {
    if (!isLoading) {
      saveToLocalStorage(WISHLIST_STORAGE_KEY, items);
    }
  }, [items, isLoading]);

  // 添加到收藏夹
  const addToWishlist = (product) => {
    setItems((prevItems) => {
      const exists = prevItems.some((item) => item.id === product.id);
      if (exists) {
        return prevItems;
      }
      return [
        ...prevItems,
        {
          ...product,
          addedAt: new Date().toISOString(),
        },
      ];
    });
  };

  // 从收藏夹移除
  const removeFromWishlist = (productId) => {
    setItems((prevItems) => prevItems.filter((item) => item.id !== productId));
  };

  // 切换收藏状态
  const toggleWishlist = (product) => {
    const exists = items.some((item) => item.id === product.id);
    if (exists) {
      removeFromWishlist(product.id);
    } else {
      addToWishlist(product);
    }
  };

  // 检查是否已收藏
  const isInWishlist = (productId) => {
    return items.some((item) => item.id === productId);
  };

  // 清空收藏夹
  const clearWishlist = () => {
    setItems([]);
  };

  const value = {
    items,
    isLoading,
    addToWishlist,
    removeFromWishlist,
    toggleWishlist,
    isInWishlist,
    clearWishlist,
    itemCount: items.length,
  };

  return (
    <WishlistContext.Provider value={value}>
      {children}
    </WishlistContext.Provider>
  );
};

// 自定义Hook
export const useWishlist = () => {
  const context = useContext(WishlistContext);

  if (!context) {
    throw new Error('useWishlist must be used within WishlistProvider');
  }

  return context;
};

ThemeContext​

src/context/ThemeContext.jsx:

import React, { createContext, useContext, useState, useEffect } from 'react';
import { loadFromLocalStorage, saveToLocalStorage } from '../utils/storage';

const ThemeContext = createContext();

const THEME_STORAGE_KEY = 'app_theme';

export const themes = {
  light: 'light',
  dark: 'dark',
  system: 'system',
};

export const ThemeProvider = ({ children }) => {
  const [theme, setThemeState] = useState(themes.system);
  const [resolvedTheme, setResolvedTheme] = useState('light');

  // 初始化主题
  useEffect(() => {
    const savedTheme = loadFromLocalStorage(THEME_STORAGE_KEY);
    if (savedTheme && Object.values(themes).includes(savedTheme)) {
      setThemeState(savedTheme);
    }
  }, []);

  // 应用主题
  useEffect(() => {
    const applyTheme = () => {
      let themeToApply = theme;

      if (theme === themes.system) {
        // 检测系统主题偏好
        const prefersDark = window.matchMedia(
          '(prefers-color-scheme: dark)'
        ).matches;
        themeToApply = prefersDark ? themes.dark : themes.light;
      }

      setResolvedTheme(themeToApply);

      // 更新DOM
      document.documentElement.setAttribute('data-theme', themeToApply);

      // 更新meta theme-color
      const metaThemeColor = document.querySelector('meta[name="theme-color"]');
      if (metaThemeColor) {
        metaThemeColor.setAttribute(
          'content',
          themeToApply === themes.dark ? '#1a1a1a' : '#ffffff'
        );
      }
    };

    applyTheme();

    // 监听系统主题变化
    if (theme === themes.system) {
      const mediaQuery = window.matchMedia('(prefers-color-scheme: dark)');
      const handleChange = () => applyTheme();
      mediaQuery.addEventListener('change', handleChange);
      return () => mediaQuery.removeEventListener('change', handleChange);
    }
  }, [theme]);

  // 切换主题
  const setTheme = (newTheme) => {
    if (Object.values(themes).includes(newTheme)) {
      setThemeState(newTheme);
      saveToLocalStorage(THEME_STORAGE_KEY, newTheme);
    }
  };

  // 切换到下一个主题
  const toggleTheme = () => {
    const themeOrder = [themes.light, themes.dark, themes.system];
    const currentIndex = themeOrder.indexOf(theme);
    const nextIndex = (currentIndex + 1) % themeOrder.length;
    setTheme(themeOrder[nextIndex]);
  };

  const value = {
    theme,
    resolvedTheme,
    setTheme,
    toggleTheme,
    isDark: resolvedTheme === themes.dark,
  };

  return (
    <ThemeContext.Provider value={value}>
      {children}
    </ThemeContext.Provider>
  );
};

// 自定义Hook
export const useTheme = () => {
  const context = useContext(ThemeContext);

  if (!context) {
    throw new Error('useTheme must be used within ThemeProvider');
  }

  return context;
};

第四階段：自定義Hooks開發​

你: 创建实用的自定义Hooks:
1. useLocalStorage - 本地存储同步
2. useDebounce - 防抖处理
3. useIntersectionObserver - 懒加载和无限滚动
4. usePrevious - 获取上一次的值
5. useMediaQuery - 响应式检测
6. useAsync - 异步状态管理

useLocalStorage​

src/hooks/useLocalStorage.js:

import { useState, useEffect, useCallback } from 'react';

export function useLocalStorage(key, initialValue) {
  // 获取初始值
  const [storedValue, setStoredValue] = useState(() => {
    try {
      const item = window.localStorage.getItem(key);
      return item ? JSON.parse(item) : initialValue;
    } catch (error) {
      console.error(`Error loading ${key} from localStorage:`, error);
      return initialValue;
    }
  });

  // 更新本地存储和状态
  const setValue = useCallback(
    (value) => {
      try {
        // 支持函数更新
        const valueToStore =
          value instanceof Function ? value(storedValue) : value;

        setStoredValue(valueToStore);

        // 保存到本地存储
        window.localStorage.setItem(key, JSON.stringify(valueToStore));
      } catch (error) {
        console.error(`Error saving ${key} to localStorage:`, error);
      }
    },
    [key, storedValue]
  );

  // 从其他标签页同步变化
  useEffect(() => {
    const handleStorageChange = (e) => {
      if (e.key === key && e.newValue !== null) {
        try {
          setStoredValue(JSON.parse(e.newValue));
        } catch (error) {
          console.error('Error parsing storage change:', error);
        }
      }
    };

    window.addEventListener('storage', handleStorageChange);
    return () => window.removeEventListener('storage', handleStorageChange);
  }, [key]);

  return [storedValue, setValue];
}

useDebounce​

src/hooks/useDebounce.js:

import { useState, useEffect } from 'react';

export function useDebounce(value, delay = 500) {
  const [debouncedValue, setDebouncedValue] = useState(value);

  useEffect(() => {
    // 设置定时器
    const timer = setTimeout(() => {
      setDebouncedValue(value);
    }, delay);

    // 清除定时器
    return () => {
      clearTimeout(timer);
    };
  }, [value, delay]);

  return debouncedValue;
}

// 使用示例:
// const [searchTerm, setSearchTerm] = useState('');
// const debouncedSearchTerm = useDebounce(searchTerm, 500);
//
// useEffect(() => {
//   // 使用防抖后的搜索词进行API调用
//   if (debouncedSearchTerm) {
//     searchProducts(debouncedSearchTerm);
//   }
// }, [debouncedSearchTerm]);

useIntersectionObserver​

src/hooks/useIntersectionObserver.js:

import { useState, useEffect, useRef } from 'react';

export function useIntersectionObserver(options = {}) {
  const [isIntersecting, setIsIntersecting] = useState(false);
  const [hasIntersected, setHasIntersected] = useState(false);
  const targetRef = useRef(null);

  useEffect(() => {
    const target = targetRef.current;
    if (!target) return;

    const observer = new IntersectionObserver(
      ([entry]) => {
        setIsIntersecting(entry.isIntersecting);

        if (entry.isIntersecting && !hasIntersected) {
          setHasIntersected(true);
        }
      },
      {
        threshold: 0.1,
        rootMargin: '0px',
        ...options,
      }
    );

    observer.observe(target);

    return () => {
      observer.unobserve(target);
    };
  }, [options.threshold, options.rootMargin, hasIntersected]);

  return [targetRef, isIntersecting, hasIntersected];
}

// 使用示例 - 懒加载图片:
// const [imgRef, isVisible] = useIntersectionObserver();
//
// <img
//   ref={imgRef}
//   src={isVisible ? imageUrl : placeholderUrl}
//   alt="Product"
// />

// 使用示例 - 无限滚动:
// const [loadMoreRef, isVisible] = useIntersectionObserver();
//
// useEffect(() => {
//   if (isVisible) {
//     loadMoreProducts();
//   }
// }, [isVisible]);

useMediaQuery​

src/hooks/useMediaQuery.js:

import { useState, useEffect } from 'react';

export function useMediaQuery(query) {
  const [matches, setMatches] = useState(() => {
    if (typeof window !== 'undefined') {
      return window.matchMedia(query).matches;
    }
    return false;
  });

  useEffect(() => {
    const mediaQuery = window.matchMedia(query);
    const handler = (e) => setMatches(e.matches);

    // 现代浏览器
    mediaQuery.addEventListener('change', handler);

    return () => {
      mediaQuery.removeEventListener('change', handler);
    };
  }, [query]);

  return matches;
}

// 使用示例:
// const isMobile = useMediaQuery('(max-width: 768px)');
// const isDarkMode = useMediaQuery('(prefers-color-scheme: dark)');
// const isPrint = useMediaQuery('print');

useAsync​

src/hooks/useAsync.js:

import { useState, useEffect, useCallback } from 'react';

export function useAsync(asyncFunction, immediate = true) {
  const [status, setStatus] = useState('idle');
  const [data, setData] = useState(null);
  const [error, setError] = useState(null);

  // 执行异步函数
  const execute = useCallback(
    async (...args) => {
      setStatus('pending');
      setData(null);
      setError(null);

      try {
        const response = await asyncFunction(...args);
        setData(response);
        setStatus('success');
        return response;
      } catch (error) {
        setError(error);
        setStatus('error');
        throw error;
      }
    },
    [asyncFunction]
  );

  // 立即执行
  useEffect(() => {
    if (immediate) {
      execute();
    }
  }, [execute, immediate]);

  return {
    execute,
    status,
    data,
    error,
    isLoading: status === 'pending',
    isError: status === 'error',
    isSuccess: status === 'success',
    isIdle: status === 'idle',
  };
}

// 使用示例:
// const { data, isLoading, error, execute } = useAsync(fetchProducts);
//
// if (isLoading) return <LoadingSpinner />;
// if (error) return <Error message={error.message} />;
// return <ProductList products={data} />;

第五階段：功能元件開發​

ProductCard元件​

src/components/features/ProductCard/ProductCard.jsx:

import React, { useState } from 'react';
import { Link } from 'react-router-dom';
import Card from '../../common/Card/Card';
import Button from '../../common/Button/Button';
import { useCart } from '../../../context/CartContext';
import { useWishlist } from '../../../context/WishlistContext';
import { useIntersectionObserver } from '../../../hooks/useIntersectionObserver';
import styles from './ProductCard.module.css';

const ProductCard = ({ product }) => {
  const { addToCart, isInCart } = useCart();
  const { toggleWishlist, isInWishlist } = useWishlist();
  const [imageLoaded, setImageLoaded] = useState(false);

  const [imgRef, isVisible] = useIntersectionObserver({
    threshold: 0.01,
    triggerOnce: true,
  });

  const inCart = isInCart(product.id);
  const inWishlist = isInWishlist(product.id);

  const handleAddToCart = (e) => {
    e.preventDefault();
    e.stopPropagation();
    addToCart(product);
  };

  const handleToggleWishlist = (e) => {
    e.preventDefault();
    e.stopPropagation();
    toggleWishlist(product);
  };

  const discount = product.discount || 0;
  const originalPrice = product.price;
  const discountedPrice = discount > 0
    ? (originalPrice * (1 - discount / 100)).toFixed(2)
    : originalPrice;

  return (
    <Link to={`/products/${product.id}`} className={styles.link}>
      <Card
        hoverable
        className={styles.card}
      >
        <div ref={imgRef} className={styles.imageContainer}>
          {isVisible && (
            <img
              src={product.image}
              alt={product.name}
              className={`${styles.image} ${imageLoaded ? styles.loaded : ''}`}
              onLoad={() => setImageLoaded(true)}
              loading="lazy"
            />
          )}
          {!imageLoaded && <div className={styles.imagePlaceholder} />}

          {discount > 0 && (
            <span className={styles.discountBadge}>
              -{discount}%
            </span>
          )}

          <button
            className={`${styles.wishlistButton} ${inWishlist ? styles.active : ''}`}
            onClick={handleToggleWishlist}
            aria-label={inWishlist ? '从收藏移除' : '添加到收藏'}
          >
            {inWishlist ? '❤️' : '🤍'}
          </button>
        </div>

        <div className={styles.content}>
          <div className={styles.category}>{product.category}</div>
          <h3 className={styles.name}>{product.name}</h3>

          <div className={styles.rating}>
            <span className={styles.stars}>
              {'★'.repeat(Math.floor(product.rating))}
              {'☆'.repeat(5 - Math.floor(product.rating))}
            </span>
            <span className={styles.reviews}>({product.reviews})</span>
          </div>

          <div className={styles.priceContainer}>
            <div className={styles.prices}>
              <span className={styles.currentPrice}>¥{discountedPrice}</span>
              {discount > 0 && (
                <span className={styles.originalPrice}>¥{originalPrice}</span>
              )}
            </div>

            <Button
              size="small"
              variant={inCart ? 'outline' : 'primary'}
              onClick={handleAddToCart}
              className={styles.cartButton}
            >
              {inCart ? '✓ 已加购' : '+ 加入'}
            </Button>
          </div>
        </div>
      </Card>
    </Link>
  );
};

export default ProductCard;

src/components/features/ProductCard/ProductCard.module.css:

.link {
  text-decoration: none;
  color: inherit;
  display: block;
}

.card {
  height: 100%;
  display: flex;
  flex-direction: column;
}

.imageContainer {
  position: relative;
  padding-top: 100%; /* 1:1 Aspect Ratio */
  overflow: hidden;
  background: var(--bg-gray);
}

.image {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.image.loaded {
  opacity: 1;
}

.imagePlaceholder {
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
}

@keyframes shimmer {
  0% {
    background-position: 200% 0;
  }
  100% {
    background-position: -200% 0;
  }
}

.discountBadge {
  position: absolute;
  top: 0.75rem;
  left: 0.75rem;
  background: var(--danger-color);
  color: white;
  padding: 0.25rem 0.75rem;
  border-radius: 0.25rem;
  font-size: 0.875rem;
  font-weight: 600;
  z-index: 1;
}

.wishlistButton {
  position: absolute;
  top: 0.75rem;
  right: 0.75rem;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  background: white;
  border: none;
  font-size: 1.25rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  transition: all 0.2s ease;
}

.wishlistButton:hover {
  transform: scale(1.1);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.wishlistButton.active {
  background: #fff5f5;
}

.content {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.category {
  font-size: 0.75rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
}

.name {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text-primary);
  margin: 0 0 0.75rem 0;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.rating {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.stars {
  color: var(--warning-color);
  letter-spacing: 0.05em;
}

.reviews {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.priceContainer {
  margin-top: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.prices {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.currentPrice {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
}

.originalPrice {
  font-size: 1rem;
  color: var(--text-secondary);
  text-decoration: line-through;
}

.cartButton {
  flex-shrink: 0;
}

/* 响应式 */
@media (max-width: 768px) {
  .content {
    padding: 1rem;
  }

  .name {
    font-size: 1rem;
  }

  .currentPrice {
    font-size: 1.25rem;
  }

  .priceContainer {
    flex-direction: column;
    align-items: flex-start;
  }

  .cartButton {
    width: 100%;
  }
}

ProductList元件(帶無限滾動)​

src/components/features/ProductList/ProductList.jsx:

import React, { useState, useEffect, useCallback } from 'react';
import ProductCard from '../ProductCard/ProductCard';
import LoadingSpinner from '../../common/LoadingSpinner/LoadingSpinner';
import { useAsync, useIntersectionObserver } from '../../../hooks';
import styles from './ProductList.module.css';

const ProductList = ({ fetchProducts, filters = {}, pageSize = 12 }) => {
  const [products, setProducts] = useState([]);
  const [page, setPage] = useState(1);
  const [hasMore, setHasMore] = useState(true);
  const [allFilters, setAllFilters] = useState(filters);

  // 使用useAsync获取数据
  const { data: newProducts, isLoading, error, execute } = useAsync(
    () => fetchProducts({ ...allFilters, page, pageSize }),
    false
  );

  // 更新过滤条件
  useEffect(() => {
    setAllFilters(filters);
    setProducts([]);
    setPage(1);
    setHasMore(true);
  }, [filters]);

  // 加载数据
  useEffect(() => {
    if (page > 0) {
      execute();
    }
  }, [page, allFilters, execute]);

  // 处理新数据
  useEffect(() => {
    if (newProducts) {
      if (page === 1) {
        setProducts(newProducts);
      } else {
        setProducts((prev) => [...prev, ...newProducts]);
      }

      // 检查是否还有更多数据
      if (newProducts.length < pageSize) {
        setHasMore(false);
      }
    }
  }, [newProducts, page, pageSize]);

  // 无限滚动
  const [loadMoreRef, isVisible] = useIntersectionObserver({
    threshold: 0.1,
  });

  useEffect(() => {
    if (isVisible && hasMore && !isLoading && page > 0) {
      setPage((prev) => prev + 1);
    }
  }, [isVisible, hasMore, isLoading, page]);

  if (error) {
    return (
      <div className={styles.error}>
        <p>加载失败: {error.message}</p>
        <button onClick={() => execute()} className={styles.retryButton}>
          重试
        </button>
      </div>
    );
  }

  return (
    <div className={styles.container}>
      <div className={styles.grid}>
        {products.map((product) => (
          <ProductCard key={product.id} product={product} />
        ))}
      </div>

      {isLoading && products.length === 0 && (
        <div className={styles.initialLoading}>
          <LoadingSpinner size="large" />
        </div>
      )}

      {isLoading && products.length > 0 && (
        <div className={styles.paginationLoading}>
          <LoadingSpinner size="medium" />
        </div>
      )}

      {!isLoading && !hasMore && products.length > 0 && (
        <div className={styles.endMessage}>
          <p>没有更多商品了</p>
        </div>
      )}

      {!isLoading && products.length === 0 && (
        <div className={styles.empty}>
          <p>暂无商品</p>
        </div>
      )}

      {hasMore && !isLoading && (
        <div ref={loadMoreRef} className={styles.loadMoreTrigger} />
      )}
    </div>
  );
};

export default ProductList;

第六階段：效能最佳化​

圖片懶載入和最佳化​

你: 实现图片优化方案:
1. 懒加载(useIntersectionObserver)
2. 响应式图片(srcset)
3. WebP格式支持
4. 图片占位符
5. BlurHash生成模糊预览

src/components/common/OptimizedImage/OptimizedImage.jsx:

import React, { useState, useRef } from 'react';
import { useIntersectionObserver } from '../../../hooks/useIntersectionObserver';
import styles from './OptimizedImage.module.css';

const OptimizedImage = ({
  src,
  alt,
  width,
  height,
  sizes = '(max-width: 768px) 100vw, (max-width: 1200px) 50vw, 33vw',
  blurHash,
  className = '',
  ...props
}) => {
  const [isLoaded, setIsLoaded] = useState(false);
  const [hasError, setHasError] = useState(false);
  const [imgRef, isVisible] = useIntersectionObserver({
    threshold: 0.01,
    triggerOnce: true,
  });

  const handleError = () => {
    setHasError(true);
  };

  const handleLoad = () => {
    setIsLoaded(true);
  };

  // 生成srcset
  const generateSrcSet = (baseSrc) => {
    const sizes = [400, 800, 1200, 1600];
    return sizes
      .map((size) => `${baseSrc}?w=${size} ${size}w`)
      .join(', ');
  };

  return (
    <div
      ref={imgRef}
      className={`${styles.container} ${className}`}
      style={{ width, height }}
    >
      {blurHash && (
        <div
          className={styles.blurHash}
          style={{ backgroundImage: `url(${blurHash})` }}
        />
      )}

      {hasError ? (
        <div className={styles.error}>
          <svg
            viewBox="0 0 24 24"
            fill="none"
            stroke="currentColor"
            strokeWidth="2"
          >
            <rect x="3" y="3" width="18" height="18" rx="2" ry="2" />
            <circle cx="8.5" cy="8.5" r="1.5" />
            <polyline points="21 15 16 10 5 21" />
          </svg>
        </div>
      ) : (
        isVisible && (
          <img
            src={src}
            alt={alt}
            srcSet={generateSrcSet(src)}
            sizes={sizes}
            loading="lazy"
            decoding="async"
            onLoad={handleLoad}
            onError={handleError}
            className={`${styles.image} ${isLoaded ? styles.loaded : ''}`}
            {...props}
          />
        )
      )}

      {!isLoaded && !hasError && (
        <div className={styles.skeleton} />
      )}
    </div>
  );
};

export default OptimizedImage;

程式碼分割和懶載入​

src/App.jsx:

import React, { lazy, Suspense } from 'react';
import { BrowserRouter, Routes, Route } from 'react-router-dom';
import LoadingSpinner from './components/common/LoadingSpinner/LoadingSpinner';
import Layout from './components/layout/Layout/Layout';

// 路由级别代码分割
const Home = lazy(() => import('./pages/Home/Home'));
const Products = lazy(() => import('./pages/Products/Products'));
const ProductDetail = lazy(() => import('./pages/ProductDetail/ProductDetail'));
const Cart = lazy(() => import('./pages/Cart/Cart'));
const Wishlist = lazy(() => import('./pages/Wishlist/Wishlist'));
const NotFound = lazy(() => import('./pages/NotFound/NotFound'));

// 加载中组件
const PageLoader = () => (
  <div style={{ minHeight: '100vh', display: 'flex', alignItems: 'center', justifyContent: 'center' }}>
    <LoadingSpinner size="large" />
  </div>
);

function App() {
  return (
    <BrowserRouter>
      <Layout>
        <Suspense fallback={<PageLoader />}>
          <Routes>
            <Route path="/" element={<Home />} />
            <Route path="/products" element={<Products />} />
            <Route path="/products/:id" element={<ProductDetail />} />
            <Route path="/cart" element={<Cart />} />
            <Route path="/wishlist" element={<Wishlist />} />
            <Route path="*" element={<NotFound />} />
          </Routes>
        </Suspense>
      </Layout>
    </BrowserRouter>
  );
}

export default App;

虛擬化長列表​

src/components/common/VirtualList/VirtualList.jsx:

import React, { useRef, useEffect, useState } from 'react';

const VirtualList = ({
  items,
  itemHeight,
  containerHeight,
  renderItem,
  overscan = 3,
}) => {
  const [scrollTop, setScrollTop] = useState(0);
  const containerRef = useRef(null);

  const totalHeight = items.length * itemHeight;
  const startIndex = Math.max(0, Math.floor(scrollTop / itemHeight) - overscan);
  const endIndex = Math.min(
    items.length - 1,
    Math.floor((scrollTop + containerHeight) / itemHeight) + overscan
  );

  const visibleItems = items.slice(startIndex, endIndex + 1);

  const handleScroll = (e) => {
    setScrollTop(e.target.scrollTop);
  };

  return (
    <div
      ref={containerRef}
      className="virtual-list-container"
      style={{ height: containerHeight, overflow: 'auto' }}
      onScroll={handleScroll}
    >
      <div style={{ height: totalHeight, position: 'relative' }}>
        {visibleItems.map((item, index) => (
          <div
            key={startIndex + index}
            style={{
              position: 'absolute',
              top: (startIndex + index) * itemHeight,
              height: itemHeight,
              width: '100%',
            }}
          >
            {renderItem(item, startIndex + index)}
          </div>
        ))}
      </div>
    </div>
  );
};

export default VirtualList;

// 使用示例:
// <VirtualList
//   items={products}
//   itemHeight={300}
//   containerHeight={600}
//   renderItem={(product, index) => (
//     <ProductCard key={product.id} product={product} />
//   )}
// />

第七階段：打包和部署最佳化​

Vite配置最佳化​

vite.config.js:

import { defineConfig } from 'vite';
import react from '@vitejs/plugin-react';
import { visualizer } from 'rollup-plugin-visualizer';
import viteCompression from 'vite-plugin-compression';
import path from 'path';

export default defineConfig({
  plugins: [
    react(),
    // Gzip压缩
    viteCompression({
      verbose: true,
      disable: false,
      threshold: 10240, // 只压缩大于10KB的文件
      algorithm: 'gzip',
      ext: '.gz',
    }),

    // Brotli压缩
    viteCompression({
      verbose: true,
      disable: false,
      threshold: 10240,
      algorithm: 'brotliCompress',
      ext: '.br',
    }),

    // 打包分析
    visualizer({
      open: false,
      gzipSize: true,
      brotliSize: true,
    }),
  ],

  resolve: {
    alias: {
      '@': path.resolve(__dirname, './src'),
    },
  },

  build: {
    // 代码分割
    rollupOptions: {
      output: {
        manualChunks: {
          // React相关
          'react-vendor': ['react', 'react-dom', 'react-router-dom'],

          // UI组件库
          'ui-vendor': ['framer-motion'],

          // 工具库
          'utils': ['axios', 'date-fns'],
        },

        // 资源文件命名
        chunkFileNames: 'assets/js/[name]-[hash].js',
        entryFileNames: 'assets/js/[name]-[hash].js',
        assetFileNames: 'assets/[ext]/[name]-[hash].[ext]',
      },
    },

    // 压缩配置
    minify: 'terser',
    terserOptions: {
      compress: {
        drop_console: true, // 删除console
        drop_debugger: true, // 删除debugger
        pure_funcs: ['console.log'], // 删除特定函数调用
      },
    },

    // chunk大小警告阈值
    chunkSizeWarningLimit: 1000,

    // 启用CSS代码分割
    cssCodeSplit: true,

    // 设置构建目标
    target: 'es2015',
  },

  // 开发服务器配置
  server: {
    port: 3000,
    host: true,
    open: true,
  },

  // 预加载配置
  optimizeDeps: {
    include: ['react', 'react-dom', 'react-router-dom'],
  },
});

環境變數配置​

.env.development:

VITE_API_URL=http://localhost:5000/api
VITE_APP_NAME=E-Commerce App
VITE_ENABLE_DEV_TOOLS=true

.env.production:

VITE_API_URL=https://api.yourapp.com
VITE_APP_NAME=E-Commerce App
VITE_ENABLE_DEV_TOOLS=false
VITE_GOOGLE_ANALYTICS_ID=G-XXXXXXXXXX

效能監控​

src/utils/performance.js:

// 性能指标收集
export const reportWebVitals = (metric) => {
  const { name, value, id } = metric;

  // 发送到分析服务
  if (window.gtag) {
    window.gtag('event', name, {
      event_category: 'Web Vitals',
      event_label: id,
      value: Math.round(name === 'CLS' ? value * 1000 : value),
      non_interaction: true,
    });
  }

  // 开发环境打印
  if (import.meta.env.DEV) {
    console.log(`[Web Vitals] ${name}:`, value);
  }
};

// 监控资源加载时间
export const measureResourceTiming = () => {
  if (!window.performance || !window.performance.getEntriesByType) {
    return;
  }

  const resources = window.performance.getEntriesByType('resource');
  const slowResources = resources.filter((r) => r.duration > 1000);

  if (slowResources.length > 0) {
    console.warn('Slow loading resources:', slowResources);
  }
};

// 监控长任务
export const measureLongTasks = () => {
  if (!window.PerformanceObserver) {
    return;
  }

  const observer = new PerformanceObserver((list) => {
    for (const entry of list.getEntries()) {
      console.warn('Long task detected:', {
        duration: entry.duration,
        startTime: entry.startTime,
      });
    }
  });

  try {
    observer.observe({ entryTypes: ['longtask'] });
  } catch (e) {
    // longtask not supported
  }
};

第八階段：測試和除錯​

元件測試示例​

ProductCard.test.jsx:

import { describe, it, expect, vi } from 'vitest';
import { render, screen, fireEvent } from '@testing-library/react';
import { BrowserRouter } from 'react-router-dom';
import ProductCard from './ProductCard';

const mockProduct = {
  id: '1',
  name: 'Test Product',
  price: 99.99,
  image: '/test-image.jpg',
  category: 'Electronics',
  rating: 4.5,
  reviews: 100,
  discount: 10,
};

const renderWithRouter = (component) => {
  return render(<BrowserRouter>{component}</BrowserRouter>);
};

describe('ProductCard', () => {
  it('renders product information correctly', () => {
    renderWithRouter(<ProductCard product={mockProduct} />);

    expect(screen.getByText('Test Product')).toBeInTheDocument();
    expect(screen.getByText('Electronics')).toBeInTheDocument();
    expect(screen.getByText('¥89.99')).toBeInTheDocument(); // 99.99 - 10%
  });

  it('adds to cart when button is clicked', () => {
    const mockAddToCart = vi.fn();

    renderWithRouter(
      <ProductCard
        product={mockProduct}
        addToCart={mockAddToCart}
      />
    );

    const addToCartButton = screen.getByText(/\+ 加入/);
    fireEvent.click(addToCartButton);

    expect(mockAddToCart).toHaveBeenCalledWith(mockProduct);
  });

  it('toggles wishlist when heart icon is clicked', () => {
    const mockToggleWishlist = vi.fn();

    renderWithRouter(
      <ProductCard
        product={mockProduct}
        toggleWishlist={mockToggleWishlist}
      />
    );

    const wishlistButton = screen.getByLabelText(/添加到收藏/);
    fireEvent.click(wishlistButton);

    expect(mockToggleWishlist).toHaveBeenCalledWith(mockProduct);
  });
});

實戰案例完整演示​

完整的電商首頁​

src/pages/Home/Home.jsx:

import React from 'react';
import { Link } from 'react-router-dom';
import Button from '../../components/common/Button/Button';
import ProductList from '../../components/features/ProductList/ProductList';
import { productService } from '../../services/productService';
import styles from './Home.module.css';

const Home = () => {
  const featuredProducts = productService.getFeatured();

  return (
    <div className={styles.home}>
      {/* Hero Section */}
      <section className={styles.hero}>
        <div className={styles.heroContent}>
          <h1 className={styles.heroTitle}>
            发现好物<br />
            <span className={styles.highlight}>品质生活</span>
          </h1>
          <p className={styles.heroSubtitle}>
            精选全球好货,为您打造优质生活体验
          </p>
          <div className={styles.heroActions}>
            <Button size="large" variant="primary">
              立即购买
            </Button>
            <Button size="large" variant="outline">
              了解更多
            </Button>
          </div>
        </div>
        <div className={styles.heroImage}>
          <img
            src="/hero-banner.jpg"
            alt="Featured Products"
            loading="eager"
          />
        </div>
      </section>

      {/* Categories */}
      <section className={styles.categories}>
        <h2 className={styles.sectionTitle}>热门分类</h2>
        <div className={styles.categoryGrid}>
          {['电子数码', '服装鞋包', '家居生活', '美妆护肤'].map((category) => (
            <Link
              key={category}
              to={`/products?category=${category}`}
              className={styles.categoryCard}
            >
              <h3>{category}</h3>
            </Link>
          ))}
        </div>
      </section>

      {/* Featured Products */}
      <section className={styles.featured}>
        <div className={styles.sectionHeader}>
          <h2 className={styles.sectionTitle}>精选商品</h2>
          <Link to="/products" className={styles.viewAll}>
            查看全部 →
          </Link>
        </div>
        <ProductList
          fetchProducts={(params) =>
            productService.getAll({ ...params, featured: true })
          }
          pageSize={8}
        />
      </section>

      {/* Newsletter */}
      <section className={styles.newsletter}>
        <div className={styles.newsletterContent}>
          <h2>订阅我们的新闻</h2>
          <p>获取最新优惠信息和产品资讯</p>
          <form className={styles.newsletterForm}>
            <input
              type="email"
              placeholder="输入您的邮箱"
              className={styles.newsletterInput}
            />
            <Button type="submit" variant="primary">
              订阅
            </Button>
          </form>
        </div>
      </section>
    </div>
  );
};

export default Home;

效能最佳化技巧總結​

1. 圖片最佳化​

✓ 使用WebP格式(比JPEG小25-35%)
✓ 响应式图片(srcset + sizes)
✓ 懒加载(IntersectionObserver)
✓ 图片压缩(tinypng.com)
✓ CDN加速
✓ BlurHash占位符

2. 程式碼最佳化​

✓ 路由级别代码分割
✓ 组件级别懒加载
✓ Tree Shaking
✓ 移除未使用的代码
✓ 压缩和混淆
✓ Polyfill按需加载

3. 渲染最佳化​

✓ React.memo防止不必要的重渲染
✓ useMemo缓存计算结果
✓ useCallback缓存函数
✓ 虚拟化长列表
✓ 防抖和节流
✓ RequestAnimationFrame优化动画

4. 網路最佳化​

✓ HTTP/2多路复用
✓ 资源预加载
✓ DNS预解析
✓ Gzip/Brotli压缩
✓ 浏览器缓存策略
✓ CDN就近访问

常見問題解決​

Q1: 如何避免記憶體洩漏?​

// ❌ 错误示例
useEffect(() => {
  const timer = setInterval(() => {
    console.log('tick');
  }, 1000);
}, []);

// ✅ 正确示例
useEffect(() => {
  const timer = setInterval(() => {
    console.log('tick');
  }, 1000);

  return () => clearInterval(timer); // 清理副作用
}, []);

Q2: 如何最佳化元件重渲染?​

// ✓ 使用React.memo
const ProductCard = React.memo(({ product }) => {
  return <div>{product.name}</div>;
});

// ✓ 使用useMemo缓存计算
const sortedProducts = useMemo(() => {
  return products.sort((a, b) => a.price - b.price);
}, [products]);

// ✓ 使用useCallback缓存函数
const handleClick = useCallback(() => {
  onProductClick(product);
}, [product, onProductClick]);

Q3: 如何處理大量資料渲染?​

// 方案1: 虚拟化
<VirtualList
  items={largeDataArray}
  itemHeight={100}
  containerHeight={600}
  renderItem={(item) => <ItemCard data={item} />}
/>

// 方案2: 分页加载
const [page, setPage] = useState(1);
const { data } = useAsync(() => fetchData(page), [page]);

// 方案3: 无限滚动
const [loadMoreRef, isVisible] = useIntersectionObserver();
useEffect(() => {
  if (isVisible) loadMore();
}, [isVisible]);

學習成果檢驗​

完成這個實戰後,你應該能夠:

✅ 建立可複用的元件庫 ✅ 實現複雜的狀態管理 ✅ 開發自定義Hooks ✅ 最佳化應用效能 ✅ 配置生產級打包 ✅ 實現響應式設計 ✅ 處理非同步操作 ✅ 進行單元測試

進階方向​

  1. 服務端渲染(SSR)

    • 遷移到Next.js
    • 實現SSG和ISR
    • SEO最佳化

  2. PWA應用

    • Service Worker
    • 離線快取
    • 推送通知

  3. 微前端架構

    • 模組聯邦
    • 獨立部署
    • 狀態共享

  4. 視覺化開發

    • 拖拽式構建器
    • 低程式碼平臺
    • 動態表單

總結​

前端開發遠不止是建立漂亮的介面。透過這個實戰案例,我們學習了:

  1. 元件化思維: 將UI拆分為可複用的元件
  2. 狀態管理: 使用Context和Hooks管理複雜狀態
  3. 效能最佳化: 從程式碼分割到圖片最佳化全方位提升
  4. 使用者體驗: 載入狀態、錯誤處理、平滑動畫
  5. 工程化: 打包最佳化、自動化測試、持續部署

Claude Code能夠顯著加速這些開發流程,讓你專注於業務邏輯和使用者體驗,而不是被重複的樣板程式碼所困擾。

結合AI輔助開發,前端開發的效率可以提升8-10倍。這正是現代前端開發的未來方向!

下一步學習​