function isValidIP(ip) {
const parts = ip.split('.');
if (parts.length !== 4) return false;
for (let part of parts) {
const num = parseInt(part);
if (isNaN(num) || num < 0 || num > 255 || part !== String(num)) return false;
}
return true;
}
function ipToLong(ip) {
const parts = ip.split('.');
return ((parseInt(parts[0]) << 24) | (parseInt(parts[1]) << 16) | (parseInt(parts[2]) << 8) | parseInt(parts[3])) >>> 0;
}
function longToIp(long) {
return [(long >>> 24) & 255, (long >>> 16) & 255, (long >>> 8) & 255, long & 255].join('.');
}
function cidrToMask(cidr) {
if (cidr === 0) return 0;
return (~((1 << (32 - cidr)) - 1)) >>> 0;
}
function maskToCidr(mask) {
let cidr = 0;
let m = mask;
while ((m & 1) === 0 && cidr < 32) { m >>>= 1; cidr++; }
return 32 - cidr;
}
function maskToDotted(mask) {
return longToIp(mask);
}
function toBinary(ip) {
return ip.split('.').map(octet => parseInt(octet).toString(2).padStart(8, '0')).join('.');
}
function calculate() {
document.getElementById('errorMsg').textContent = '';
const ipStr = document.getElementById('ipInput').value.trim();
const maskStr = document.getElementById('maskInput').value.trim();
if (!isValidIP(ipStr)) {
document.getElementById('errorMsg').textContent = '❌ 无效的IP地址格式';
return;
}
let cidr;
let maskLong;
if (maskStr.startsWith('/')) {
cidr = parseInt(maskStr.substring(1));
if (isNaN(cidr) || cidr < 0 || cidr > 32) {
document.getElementById('errorMsg').textContent = '❌ 无效的CIDR前缀 (0-32)';
return;
}
maskLong = cidrToMask(cidr);
} else if (isValidIP(maskStr)) {
maskLong = ipToLong(maskStr);
// 验证是否是有效子网掩码
const binary = maskLong.toString(2).padStart(32, '0');
const zeroFound = binary.indexOf('0');
const oneAfterZero = zeroFound >= 0 ? binary.indexOf('1', zeroFound) : -1;
if (oneAfterZero >= 0) {
document.getElementById('errorMsg').textContent = '❌ 无效的子网掩码（非连续）';
return;
}
cidr = maskToCidr(maskLong);
} else {
document.getElementById('errorMsg').textContent = '❌ 无效的子网掩码格式，请使用如 255.255.255.0 或 /24';
return;
}
const ipLong = ipToLong(ipStr);
const networkLong = (ipLong & maskLong) >>> 0;
const broadcastLong = (networkLong | (~maskLong)) >>> 0;
const firstHostLong = networkLong + 1;
const lastHostLong = broadcastLong - 1;
const totalHosts = Math.pow(2, 32 - cidr);
const usableHosts = cidr <= 30 ? totalHosts - 2 : (cidr === 31 ? 2 : 1);
const wildcardLong = (~maskLong) >>> 0;
const ipClass = getIPClass(ipStr);
const isPrivate = checkPrivate(ipStr);
const ipType = getIPType(ipStr);
const results = [
{ label: 'IP地址', value: ipStr },
{ label: '子网掩码', value: maskToDotted(maskLong) },
{ label: 'CIDR前缀', value: '/' + cidr },
{ label: '网络地址', value: longToIp(networkLong), copy: true },
{ label: '广播地址', value: longToIp(broadcastLong), copy: true },
{ label: '可用主机范围', value: cidr === 32 ? ipStr : (cidr === 31 ? `${longToIp(firstHostLong)} - ${longToIp(lastHostLong+1)}` : `${longToIp(firstHostLong)} - ${longToIp(lastHostLong)}`) },
{ label: '总主机数', value: totalHosts.toLocaleString() },
{ label: '可用主机数', value: usableHosts.toLocaleString() },
{ label: '通配符掩码', value: longToIp(wildcardLong) },
{ label: 'IP类别', value: ipClass },
{ label: 'IP类型', value: isPrivate ? '私有地址' : '公有地址' },
{ label: '特殊类型', value: ipType || '-' }
];
let gridHtml = '';
results.forEach(r => {
gridHtml += `${r.label}
${r.value}${r.copy ? '' : ''}
| IP地址 | ${ipStr} |
| 子网掩码 | ${maskToDotted(maskLong)} |
| CIDR表示法 | ${longToIp(networkLong)}/${cidr} |
| 网络地址 | ${longToIp(networkLong)} |
| 第一个可用主机 | ${cidr === 32 ? '-' : (cidr === 31 ? longToIp(firstHostLong) : longToIp(firstHostLong))} |
| 最后一个可用主机 | ${cidr <= 30 ? longToIp(lastHostLong) : (cidr === 31 ? longToIp(lastHostLong+1) : '-')} |
| 广播地址 | ${cidr === 32 ? '-' : longToIp(broadcastLong)} |
| 总IP数量 | ${totalHosts.toLocaleString()} |
| 可用主机数 | ${usableHosts.toLocaleString()} |
| IP类别 | ${ipClass} |
| 地址类型 | ${isPrivate ? '私有' : '公有'} |
`;
document.getElementById('subnetCard').style.display = 'block';
}
function getIPClass(ip) {
const first = parseInt(ip.split('.')[0]);
if (first < 128) return 'A类 (1-126)';
if (first < 192) return 'B类 (128-191)';
if (first < 224) return 'C类 (192-223)';
if (first < 240) return 'D类 (组播 224-239)';
return 'E类 (保留 240-255)';
}
function checkPrivate(ip) {
const parts = ip.split('.').map(Number);
if (parts[0] === 10) return true;
if (parts[0] === 172 && parts[1] >= 16 && parts[1] <= 31) return true;
if (parts[0] === 192 && parts[1] === 168) return true;
if (parts[0] === 127) return true;
return false;
}
function getIPType(ip) {
const long = ipToLong(ip);
if (long === ipToLong('0.0.0.0')) return '默认路由/本网络';
if (long === ipToLong('255.255.255.255')) return '受限广播';
const parts = ip.split('.').map(Number);
if (parts[0] === 127) return '回环地址';
if (parts[0] >= 224 && parts[0] <= 239) return '组播地址';
if (parts[0] >= 240) return '保留地址';
if (ip.startsWith('169.254.')) return '链路本地地址';
return '';
}
function copyText(text) {
navigator.clipboard.writeText(text).then(() => alert('已复制: ' + text));
}
// 回车触发计算
document.getElementById('ipInput').addEventListener('keypress', e => { if(e.key==='Enter') calculate(); });
document.getElementById('maskInput').addEventListener('keypress', e => { if(e.key==='Enter') calculate(); });
// 页面加载时自动计算一次
window.onload = calculate;