获取客户端局域网ip

    <script> 
    function getIPs(callback){ 
        var ip_dups = {}; 
      
        //compatibility for firefox and chrome 
        var RTCPeerConnection = window.RTCPeerConnection 
            || window.mozRTCPeerConnection 
            || window.webkitRTCPeerConnection; 
        var mediaConstraints = { 
            optional: [{RtpDataChannels: true}] 
        }; 
      
        //firefox already has a default stun server in about:config 
        //    media.peerconnection.default_iceservers = 
        //    [{"url": "stun:stun.services.mozilla.com"}] 
        var servers = undefined; 
      
        //add same stun server for chrome 
        if(window.webkitRTCPeerConnection) 
            servers = {iceServers: [{urls: "stun:stun.services.mozilla.com"}]}; 
      
        //construct a new RTCPeerConnection 
        var pc = new RTCPeerConnection(servers, mediaConstraints); 
      
        //listen for candidate events 
        pc.onicecandidate = function(ice){ 
   
            //skip non-candidate events 
            if(ice.candidate && ice.candidate.candidate){ 
    
      
                //match just the IP address 
                var ip_regex = /([0-9]{1,3}(.[0-9]{1,3}){3})/ 
                var ip_addr = ip_regex.exec(ice.candidate.candidate)[1]; 
      
                //remove duplicates 
                if(ip_dups[ip_addr] !== undefined) 
                    callback(ip_addr); 
      
                ip_dups[ip_addr] = true; 
            } 
        }; 
      
        //create a bogus data channel 
        pc.createDataChannel(""); 
      
        //create an offer sdp 
        pc.createOffer(function(result){ 
      
            //trigger the stun server request 
            pc.setLocalDescription(result, function(){ },function(){}); 
      
        }, function(){}); 
    } 
      
    //Test: Print the IP addresses into the console 
    getIPs(function(ip){console.log(ip);}); 
     
    </script>