通过js获取用户网络ip地址

<!DOCTYPE html>
<html>
 
<head>
    <meta charset="utf-8">
    <title>js获取本地ip</title>
</head>
 
<body>
    <script>
        var xmlhttp;
        if (window.XMLHttpRequest) {
            xmlhttp = new XMLHttpRequest();
        } else {
            xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        }
        xmlhttp.open("get", "https://api.ipify.org?format=json", false);
        xmlhttp.send();
        var item = JSON.parse(xmlhttp.responseText);
        console.log(item)
        alert(item.ip)
    </script>
</body>
 
</html>