对上面答案的改进，原因如下:

Code should be as self-explanatory as possible. Enumerating over an array using for...in... should be avoided. for...in... enumeration should be validated to ensure the object's being enumerated over contains the property you're looking for. As JavaScript is loosely typed and the for...in... can be handed any arbitrary object to handle; it's safer to validate the property we're looking for is available. var os = require('os'), interfaces = os.networkInterfaces(), address, addresses = [], i, l, interfaceId, interfaceArray; for (interfaceId in interfaces) { if (interfaces.hasOwnProperty(interfaceId)) { interfaceArray = interfaces[interfaceId]; l = interfaceArray.length; for (i = 0; i < l; i += 1) { address = interfaceArray[i]; if (address.family === 'IPv4' && !address.internal) { addresses.push(address.address); } } } } console.log(addresses);

下面是一段Node.js代码，它将解析ifconfig的输出并(异步地)返回找到的第一个IP地址:

(它只在Mac OS X v10.6 (Snow Leopard)上测试;我希望它也能在Linux上运行。)

var getNetworkIP = (function () {
    var ignoreRE = /^(127\.0\.0\.1|::1|fe80(:1)?::1(%.*)?)$/i;

    var exec = require('child_process').exec;
    var cached;
    var command;
    var filterRE;

    switch (process.platform) {
        // TODO: implement for OSes without the ifconfig command
        case 'darwin':
             command = 'ifconfig';
             filterRE = /\binet\s+([^\s]+)/g;
             // filterRE = /\binet6\s+([^\s]+)/g; // IPv6
             break;
        default:
             command = 'ifconfig';
             filterRE = /\binet\b[^:]+:\s*([^\s]+)/g;
             // filterRE = /\binet6[^:]+:\s*([^\s]+)/g; // IPv6
             break;
    }

    return function (callback, bypassCache) {
        // Get cached value
        if (cached && !bypassCache) {
            callback(null, cached);
            return;
        }

        // System call
        exec(command, function (error, stdout, sterr) {
            var ips = [];
            // Extract IP addresses
            var matches = stdout.match(filterRE);

            // JavaScript doesn't have any lookbehind regular expressions, so we need a trick
            for (var i = 0; i < matches.length; i++) {
                ips.push(matches[i].replace(filterRE, '$1'));
            }

            // Filter BS
            for (var i = 0, l = ips.length; i < l; i++) {
                if (!ignoreRE.test(ips[i])) {
                    //if (!error) {
                        cached = ips[i];
                    //}
                    callback(error, ips[i]);
                    return;
                }
            }
            // Nothing found
            callback(error, null);
        });
    };
})();

使用的例子:

getNetworkIP(function (error, ip) {
    console.log(ip);
    if (error) {
        console.log('error:', error);
    }
}, false);

如果第二个参数为true，函数将每次执行一次系统调用;否则使用缓存的值。

更新版本

返回所有本地网络地址的数组。

在Ubuntu 11.04 (Natty Narwhal)和Windows XP 32上测试

var getNetworkIPs = (function () {
    var ignoreRE = /^(127\.0\.0\.1|::1|fe80(:1)?::1(%.*)?)$/i;

    var exec = require('child_process').exec;
    var cached;
    var command;
    var filterRE;

    switch (process.platform) {
        case 'win32':
        //case 'win64': // TODO: test
            command = 'ipconfig';
            filterRE = /\bIPv[46][^:\r\n]+:\s*([^\s]+)/g;
            break;
        case 'darwin':
            command = 'ifconfig';
            filterRE = /\binet\s+([^\s]+)/g;
            // filterRE = /\binet6\s+([^\s]+)/g; // IPv6
            break;
        default:
            command = 'ifconfig';
            filterRE = /\binet\b[^:]+:\s*([^\s]+)/g;
            // filterRE = /\binet6[^:]+:\s*([^\s]+)/g; // IPv6
            break;
    }

    return function (callback, bypassCache) {
        if (cached && !bypassCache) {
            callback(null, cached);
            return;
        }

        // System call
        exec(command, function (error, stdout, sterr) {
            cached = [];
            var ip;
            var matches = stdout.match(filterRE) || [];
            //if (!error) {
            for (var i = 0; i < matches.length; i++) {
                ip = matches[i].replace(filterRE, '$1')
                if (!ignoreRE.test(ip)) {
                    cached.push(ip);
                }
            }
            //}
            callback(error, cached);
        });
    };
})();

使用举例:升级版本

getNetworkIPs(function (error, ip) {
console.log(ip);
if (error) {
    console.log('error:', error);
}
}, false);

您的本地IP地址总是127.0.0.1。

然后是网络IP地址，可以从ifconfig (*nix)或ipconfig (win)中获取。这只在本地网络中有用。

然后是你的外部/公共IP地址，你只能通过某种方式向路由器请求它，或者你可以设置一个外部服务，在收到请求时返回客户端IP地址。还有其他类似的服务，比如whatismyip.com。

在某些情况下(例如，如果您有一个广域网连接)，网络IP地址和公共IP地址是相同的，并且都可以用于外部访问您的计算机。

如果您的网络和公共IP地址不同，您可能需要让网络路由器将所有传入连接转发到您的网络IP地址。

2013年更新:

现在有了一种新的方法。你可以检查连接的套接字对象的localAddress属性，例如net.socket.localAddress。它返回套接字一端的地址。

最简单的方法是打开一个随机端口并监听它，然后获取您的地址并关闭套接字。

2015年更新:

前面的已经不管用了。

这是对已接受答案的修改，它不考虑vEthernet IP地址，如Docker等。

/**
 * Get local IP address, while ignoring vEthernet IP addresses (like from Docker, etc.)
 */
let localIP;
var os = require('os');
var ifaces = os.networkInterfaces();
Object.keys(ifaces).forEach(function (ifname) {
   var alias = 0;

   ifaces[ifname].forEach(function (iface) {
      if ('IPv4' !== iface.family || iface.internal !== false) {
         // Skip over internal (i.e. 127.0.0.1) and non-IPv4 addresses
         return;
      }

      if(ifname === 'Ethernet') {
         if (alias >= 1) {
            // This single interface has multiple IPv4 addresses
            // console.log(ifname + ':' + alias, iface.address);
         } else {
            // This interface has only one IPv4 address
            // console.log(ifname, iface.address);
         }
         ++alias;
         localIP = iface.address;
      }
   });
});
console.log(localIP);

这将返回一个类似192.168.2.169的IP地址，而不是10.55.1.1。

公认的答案是异步的。我想要一个同步版本:

var os = require('os');
var ifaces = os.networkInterfaces();

console.log(JSON.stringify(ifaces, null, 4));

for (var iface in ifaces) {
  var iface = ifaces[iface];
  for (var alias in iface) {
    var alias = iface[alias];

    console.log(JSON.stringify(alias, null, 4));

    if ('IPv4' !== alias.family || alias.internal !== false) {
      debug("skip over internal (i.e. 127.0.0.1) and non-IPv4 addresses");
      continue;
    }
    console.log("Found IP address: " + alias.address);
    return alias.address;
  }
}
return false;

Use:

var os = require('os');
var networkInterfaces = os.networkInterfaces();
var arr = networkInterfaces['Local Area Connection 3']
var ip = arr[1].address;