我们可以在node js中检查这段代码

const os       = require('os');
const interfaces = os.networkInterfaces();

let addresses = [];

for (var k in interfaces) {

    for (var k2 in interfaces[k]) {

        const address = interfaces[k][k2];

        if ( (address.family === 'IPv4' || address.family === 'IPv6')  && 
            !address.internal) {

            addresses.push(address.address);

        }
    }
}
console.log(addresses);

我们可以在node js中检查这段代码

const os       = require('os');
const interfaces = os.networkInterfaces();

let addresses = [];

for (var k in interfaces) {

    for (var k2 in interfaces[k]) {

        const address = interfaces[k][k2];

        if ( (address.family === 'IPv4' || address.family === 'IPv6')  && 
            !address.internal) {

            addresses.push(address.address);

        }
    }
}
console.log(addresses);

我使用这个ipv4格式

req.connection.remoteAddress.split(':').slice(-1)[0]

获取ip地址有两种方式:

让IP = req.ip 让ip = req.connection.remoteAddress;

但上述方法存在一个问题。

如果你在Nginx或任何代理程序后面运行你的应用程序，每个IP地址将是127.0.0.1。

因此，获取user的ip地址的最佳方案是:-

let ip = req.header('x-forwarded-for') || req.connection.remoteAddress;

var ip = req.headers['x-forwarded-for'] ||
     req.socket.remoteAddress ||
     null;

请注意，有时您可以在req.headers['x-forwarded-for']中获得多个IP地址。此外，并不总是设置x-forward -for报头，这可能会抛出错误。

该字段的一般格式为:

x-forward -for: client, proxy1, proxy2, proxy3

其中的值是一个逗号+空格分隔的IP地址列表，最左边是原始客户端，每个传递请求的后续代理添加接收请求的IP地址。在本例中，请求通过proxy1、proxy2和proxy3传递。Proxy3显示为请求的远程地址。

这是Arnav Gupta提出的解决方案，Martin在下面的评论中为未设置x-forward -for的情况提出了修复建议:

var ip = (req.headers['x-forwarded-for'] || '').split(',').pop().trim() || 
         req.socket.remoteAddress

使用现代JS的建议:

仅在设置时处理x-forward -for，如果设置了，则取第一个地址 其他参数使用可选链接(?.)

const parseIp = (req) =>
    req.headers['x-forwarded-for']?.split(',').shift()
    || req.socket?.remoteAddress

console.log(parseIp(req))
// => 127.0.0.1

以下函数涵盖了所有的情况，将会有所帮助

var ip;
if (req.headers['x-forwarded-for']) {
    ip = req.headers['x-forwarded-for'].split(",")[0];
} else if (req.connection && req.connection.remoteAddress) {
    ip = req.connection.remoteAddress;
} else {
    ip = req.ip;
}console.log("client IP is *********************" + ip);