截取url中的域名

function extractDomain(url) {
    const regex = /^(?:https?:\/\/)?(?:[^@\n]+@)?(?:www\.)?([^:\/\n]+)/;
    const match = url.match(regex);
    return match ? match[1] : null;
}

const url = 'https://www.example.com/path/to/resource?query=param';
const domain = extractDomain(url);
console.log(domain); // 输出: www.example.com

function extractDomain(url) {
    try {
        const parsedUrl = new URL(url);
        return parsedUrl.hostname;
    } catch (e) {
        return null;
    }
}

const url = 'https://www.example.com/path/to/resource?query=param';
const domain = extractDomain(url);
console.log(domain); // 输出: www.example.com

function isValidUrl(url) {
    try {
        new URL(url);
        return true;
    } catch (e) {
        return false;
    }
}

const url = 'invalid-url';
if (isValidUrl(url)) {
    const domain = extractDomain(url);
    console.log(domain);
} else {
    console.log('Invalid URL');
}

async function checkDomainReachability(url) {
    try {
        const response = await fetch(url, { method: 'HEAD' });
        return response.ok;
    } catch (e) {
        return false;
    }
}

const url = 'https://www.example.com';
checkDomainReachability(url).then(reachable => {
    if (reachable) {
        const domain = extractDomain(url);
        console.log(domain);
    } else {
        console.log('Domain is not reachable');
    }
});