面试题：TypeScript 正则表达式类型安全验证器的复杂规则封装

定义验证规则类型：

type ValidationRule<T> = {
    regex: RegExp;
    message: string;
    validate: (value: unknown) => value is T;
};

创建验证器模块：

const validators: Record<string, ValidationRule<any>> = {};

export const addValidator = <T>(name: string, rule: ValidationRule<T>) => {
    validators[name] = rule;
};

export const validate = <T>(name: string, value: unknown): value is T => {
    const rule = validators[name];
    if (!rule) {
        throw new Error(`Validator '${name}' not found`);
    }
    return rule.validate(value);
};

添加具体验证规则示例：

日期格式验证：

const dateRegex = /^\d{4}-(0[1 - 9]|1[0 - 2])-(0[1 - 9]|[12][0 - 9]|3[01])$/;
const dateValidate = (value: unknown): value is string => {
    return typeof value ==='string' && dateRegex.test(value);
};
addValidator('date', {
    regex: dateRegex,
    message: 'Invalid date format. Expected YYYY - MM - DD',
    validate: dateValidate
});

手机号码格式验证：

const phoneRegex = /^1\d{10}$/;
const phoneValidate = (value: unknown): value is string => {
    return typeof value ==='string' && phoneRegex.test(value);
};
addValidator('phone', {
    regex: phoneRegex,
    message: 'Invalid phone number format. Expected 11 - digit number starting with 1',
    validate: phoneValidate
});

使用验证器：

const testDate = '2023 - 10 - 05';
if (validate('date', testDate)) {
    console.log('Date is valid');
} else {
    console.log('Date is invalid');
}

const testPhone = '12345678901';
if (validate('phone', testPhone)) {
    console.log('Phone number is valid');
} else {
    console.log('Phone number is invalid');
}

以上代码通过定义验证规则类型，创建可复用的验证器模块，实现了可以方便添加新验证规则，并在调用验证函数时保证参数类型正确的功能。addValidator 方法用于添加新的验证规则，validate 方法用于执行验证。通过类型断言和类型守卫确保类型安全。

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面试题：TypeScript 正则表达式类型安全验证器的复杂规则封装

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