js 检查非法字符

function checkIllegalCharacters(input, allowedPattern) {
    const regex = new RegExp(`[^${allowedPattern}]`);
    return regex.test(input);
}

// 示例：检查用户名是否包含非法字符（只允许字母、数字和下划线）
const username = "user_name123";
const allowedPattern = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";

if (checkIllegalCharacters(username, allowedPattern)) {
    console.log("用户名包含非法字符");
} else {
    console.log("用户名合法");
}

function replaceIllegalCharacters(input, allowedPattern) {
    const regex = new RegExp(`[^${allowedPattern}]`, 'g');
    return input.replace(regex, '');
}

const username = "user#name123";
const sanitizedUsername = replaceIllegalCharacters(username, allowedPattern);
console.log(sanitizedUsername); // 输出: username123