我使用WebRTC連接了2個Chrome瀏覽器。我offer在第一個signalR客戶端上創建并將其發送給第二個客戶端，如下所示：function initiate_call() {callerPeerConn = new RTCPeerConnection(peerConnCfg);callerPeerConn.ontrack = function (event) {    console.log('caller recived new stream');    remoteVideo.srcObject = event.streams[0];    console.log(event);}navigator.mediaDevices.getUserMedia({ audio: true, video: true })    .then(function (stream) {        localVideo.srcObject = stream;        for (const track of stream.getTracks()) {            callerPeerConn.addTrack(track, stream);        }        return callerPeerConn.createOffer();    })    .then(    function (offer) {        var off = new RTCSessionDescription(offer);        callerPeerConn.setLocalDescription(            new RTCSessionDescription(off),            function () {                // invite to video chat                console.log('send offer');            },            function (err) {                console.log(err.message);            }        )    });}當我使用第二個瀏覽器時，offer他使用setLocalDescription并嘗試創建，而answer不是像這樣將其發送給呼叫者：function accept_send_answer(){    calleePeerConn = new RTCPeerConnection(peerConnCfg);calleePeerConn.ontrack = function (event) {    console.log('callee accept offer and got streams');    remoteVideo.srcObject = event.streams[0];}calleePeerConn.setRemoteDescription(offer)    .then(function () {        return navigator.mediaDevices.getUserMedia({ audio: true, video: true });    })    .then(function (stream) {        localVideo.srcObject = stream;         for (const track of stream.getTracks()) {            calleePeerConn.addTrack(track, stream);        }        return calleePeerConn.createAnswer();    })    })    .catch(function (err) {        console.log(err.message);    });}