Tips & Tricks

如何使用 Claude Code 优化无障碍访问

学习如何使用 Claude Code 优化无障碍访问。包含实用代码示例和分步指导。

使用 Claude Code 进行无障碍适配的优势

Web 无障碍访问非常重要,但理解 WCAG 标准和正确使用 ARIA 属性却很复杂。Claude Code 能够基于无障碍最佳实践高效生成代码,并对现有代码进行审计。

现有代码的无障碍审计

> 从无障碍角度审查 src/components/ 下的所有组件。
> 按照 WCAG 2.1 AA 标准检查,列出问题和修复建议。

Claude Code 能检测出以下问题:

  • 图片缺少 alt 属性
  • 表单元素未关联 label 元素
  • 颜色对比度不足
  • 存在无法通过键盘操作的交互元素
  • ARIA 属性使用不当

生成无障碍组件

模态对话框

> 创建一个无障碍的模态对话框。
> 实现焦点陷阱、ESC 键关闭、背景滚动锁定。
import { useEffect, useRef, useCallback } from 'react';

interface ModalProps {
  isOpen: boolean;
  onClose: () => void;
  title: string;
  children: React.ReactNode;
}

function Modal({ isOpen, onClose, title, children }: ModalProps) {
  const modalRef = useRef<HTMLDivElement>(null);
  const previousFocus = useRef<HTMLElement | null>(null);

  // 焦点陷阱
  const trapFocus = useCallback((e: KeyboardEvent) => {
    if (!modalRef.current) return;

    const focusable = modalRef.current.querySelectorAll<HTMLElement>(
      'a[href], button:not([disabled]), input:not([disabled]), select, textarea, [tabindex]:not([tabindex="-1"])'
    );

    const first = focusable[0];
    const last = focusable[focusable.length - 1];

    if (e.key === 'Tab') {
      if (e.shiftKey && document.activeElement === first) {
        e.preventDefault();
        last.focus();
      } else if (!e.shiftKey && document.activeElement === last) {
        e.preventDefault();
        first.focus();
      }
    }

    if (e.key === 'Escape') onClose();
  }, [onClose]);

  useEffect(() => {
    if (isOpen) {
      previousFocus.current = document.activeElement as HTMLElement;
      document.body.style.overflow = 'hidden';
      document.addEventListener('keydown', trapFocus);

      // 聚焦到模态框内第一个可聚焦元素
      setTimeout(() => {
        modalRef.current?.querySelector<HTMLElement>('[autofocus], button')?.focus();
      }, 0);
    }

    return () => {
      document.body.style.overflow = '';
      document.removeEventListener('keydown', trapFocus);
      previousFocus.current?.focus();
    };
  }, [isOpen, trapFocus]);

  if (!isOpen) return null;

  return (
    <div
      className="fixed inset-0 z-50 flex items-center justify-center"
      role="presentation"
    >
      <div
        className="fixed inset-0 bg-black/50"
        aria-hidden="true"
        onClick={onClose}
      />
      <div
        ref={modalRef}
        role="dialog"
        aria-modal="true"
        aria-labelledby="modal-title"
        className="relative z-10 mx-4 w-full max-w-lg rounded-lg bg-white p-6 shadow-xl dark:bg-gray-800"
      >
        <h2 id="modal-title" className="text-xl font-bold mb-4">
          {title}
        </h2>
        {children}
        <button
          onClick={onClose}
          aria-label="Close"
          className="absolute right-4 top-4 rounded-full p-1 hover:bg-gray-100 dark:hover:bg-gray-700"
        >
          <svg aria-hidden="true" className="h-5 w-5" viewBox="0 0 20 20" fill="currentColor">
            <path d="M4.293 4.293a1 1 0 011.414 0L10 8.586l4.293-4.293a1 1 0 111.414 1.414L11.414 10l4.293 4.293a1 1 0 01-1.414 1.414L10 11.414l-4.293 4.293a1 1 0 01-1.414-1.414L8.586 10 4.293 5.707a1 1 0 010-1.414z" />
          </svg>
        </button>
      </div>
    </div>
  );
}

无障碍下拉菜单

function DropdownMenu({ label, items }: { label: string; items: MenuItem[] }) {
  const [isOpen, setIsOpen] = useState(false);
  const [activeIndex, setActiveIndex] = useState(-1);
  const menuRef = useRef<HTMLUListElement>(null);

  const handleKeyDown = (e: React.KeyboardEvent) => {
    switch (e.key) {
      case 'ArrowDown':
        e.preventDefault();
        setActiveIndex(prev => Math.min(prev + 1, items.length - 1));
        break;
      case 'ArrowUp':
        e.preventDefault();
        setActiveIndex(prev => Math.max(prev - 1, 0));
        break;
      case 'Enter':
      case ' ':
        e.preventDefault();
        if (activeIndex >= 0) items[activeIndex].onClick();
        setIsOpen(false);
        break;
      case 'Escape':
        setIsOpen(false);
        break;
    }
  };

  return (
    <div className="relative" onKeyDown={handleKeyDown}>
      <button
        aria-haspopup="true"
        aria-expanded={isOpen}
        onClick={() => setIsOpen(!isOpen)}
      >
        {label}
      </button>
      {isOpen && (
        <ul ref={menuRef} role="menu" className="absolute mt-1 rounded-md border bg-white shadow-lg dark:bg-gray-800">
          {items.map((item, i) => (
            <li
              key={i}
              role="menuitem"
              tabIndex={-1}
              className={`cursor-pointer px-4 py-2 ${i === activeIndex ? 'bg-blue-100 dark:bg-blue-900' : ''}`}
              onClick={item.onClick}
            >
              {item.label}
            </li>
          ))}
        </ul>
      )}
    </div>
  );
}

表单无障碍

> 将联系表单重构为无障碍版本。
> 确保验证错误信息能被屏幕阅读器识别。
function ContactForm() {
  const [errors, setErrors] = useState<Record<string, string>>({});

  return (
    <form aria-label="联系表单" noValidate>
      <div className="mb-4">
        <label htmlFor="name" className="block font-medium mb-1">
          姓名 <span aria-label="required">*</span>
        </label>
        <input
          id="name"
          type="text"
          required
          aria-required="true"
          aria-invalid={!!errors.name}
          aria-describedby={errors.name ? 'name-error' : undefined}
          className="w-full rounded border p-2"
        />
        {errors.name && (
          <p id="name-error" role="alert" className="mt-1 text-sm text-red-600">
            {errors.name}
          </p>
        )}
      </div>

      <div className="mb-4">
        <label htmlFor="email" className="block font-medium mb-1">
          邮箱地址 <span aria-label="required">*</span>
        </label>
        <input
          id="email"
          type="email"
          required
          aria-required="true"
          aria-invalid={!!errors.email}
          aria-describedby="email-hint email-error"
          className="w-full rounded border p-2"
        />
        <p id="email-hint" className="mt-1 text-xs text-gray-500">
          e.g., [email protected]
        </p>
        {errors.email && (
          <p id="email-error" role="alert" className="mt-1 text-sm text-red-600">
            {errors.email}
          </p>
        )}
      </div>

      <button type="submit" className="rounded bg-blue-600 px-4 py-2 text-white">
        提交
      </button>
    </form>
  );
}

引入自动化测试

> 使用 jest-axe 添加无障碍测试。
import { render } from '@testing-library/react';
import { axe, toHaveNoViolations } from 'jest-axe';

expect.extend(toHaveNoViolations);

describe('Modal accessibility', () => {
  it('should have no accessibility violations', async () => {
    const { container } = render(
      <Modal isOpen={true} onClose={() => {}} title="Test Modal">
        <p>Content</p>
      </Modal>
    );
    const results = await axe(container);
    expect(results).toHaveNoViolations();
  });
});

总结

借助 Claude Code,你可以高效完成从生成符合 WCAG 标准的无障碍组件到审计现有代码的全流程。通过钩子功能自动执行无障碍测试也是一个不错的选择。详情请参阅钩子功能指南。日常开发流程中的实用技巧请查看生产力提升 3 倍的 Tips

Claude Code 的详细信息请参阅 Anthropic 官方文档。WCAG 指南的详细内容请参阅 W3C WCAG 2.1

#Claude Code #accessibility #WCAG #a11y #React