📝 第七章：字符串与正则表达式

// 传统字符串
const name = 'John';
const message = 'Hello, ' + name + '!'; // 'Hello, John!'

// 模板字符串
const message2 = `Hello, ${name}!`; // 'Hello, John!'

// 多行字符串
const multiLine = `
    Hello
    World
`;

// 表达式
const a = 10;
const b = 20;
const sum = `${a} + ${b} = ${a + b}`; // '10 + 20 = 30'

// 标签函数
function highlight(strings, ...values) {
    let result = '';
    strings.forEach((string, index) => {
        result += string;
        if (values[index] !== undefined) {
            result += `<span style="background: yellow;">${values[index]}`;
        }
    });
    return result;
}

const name = 'John';
const age = 30;
const result = highlight`Hello, ${name}! You are ${age} years old.`;
console.log(result); // Hello, <span style="background: yellow;">John! You are <span style="background: yellow;">30 years old.

// 字面量语法
const regex1 = /pattern/flags;

// 构造函数语法
const regex2 = new RegExp('pattern', 'flags');

// 示例
const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
const phoneRegex = /^1[3-9]\d{9}$/;

// test() - 检查是否匹配
const regex = /\d+/;
console.log(regex.test('123')); // true

// exec() - 执行匹配
const result = regex.exec('abc123def456');
console.log(result); // ['123', index: 3, input: 'abc123def456', groups: undefined]

// match() - 字符串方法
const str = 'abc123def456';
console.log(str.match(/\d+/g)); // ['123', '456']

// replace() - 替换
const replaced = str.replace(/\d+/g, 'X');
console.log(replaced); // 'abcXdefX'

// /v 标志 - Unicode 属性类增强
const regex = /\p{Emoji}/v;
console.log(regex.test('😊')); // true

const regex2 = /\p{Script=Han}/v; // 匹配汉字
console.log(regex2.test('你好')); // true

// 重复命名捕获组
const regex = /(?<digit>\d)+/;
const result = regex.exec('12345');
console.log(result.groups.digit); // '5'（最后一个匹配的数字）

// 在 replace 中使用
const str = '123-456-789';
const replaced = str.replace(/(?<area>\d{3})-(?<local>\d{3})-(?<line>\d{3})/, 'Area: $<area>, Local: $<local>, Line: $<line>');
console.log(replaced); // 'Area: 123, Local: 456, Line: 789'