WebRTC onicecandidate 永远不会在 chrome 中触发

Question

我的 webrtc 网络应用程序从未启动

onicecandidate()

。 当我查看本地（Webrtc 对象）对象时，设置了

localdescription

和

remotedescription

。 在 Firefox 中，它会触发

onicecandidate()

但

event.candidate

为空。

我尝试了几个小时来解决这个问题，但我做不到

有人能解决这个问题吗？

如何才能触发

onicecandidate()

事件？

      let local = new RTCPeerConnection();
      let remote = new RTCPeerConnection();
      try {
        local.createOffer().then(function(sdp) {
          console.log("Offer Created by Local: " + sdp.sdp);
          local.setLocalDescription(sdp);
          remote.setRemoteDescription(sdp);
          
          remote.createAnswer().then(function(sdp){
            console.log("Answer Created by Remote: " + sdp.sdp);
            remote.setLocalDescription(sdp);
            local.setRemoteDescription(sdp);
            local.onicecandidate = localicecandidate;
            remote.onicecandidate = remoteicecandidate;

            let channel = local.createDataChannel("channel");
            channel.onopen = function(event) {
              console.log("Channel opened");
            }
            channel.onmessgae = function(event) {
              console.log(event.data);
            }

            remote.ondatachannel = function(event) {
              let channel = event.channel;
              channel.onopen = function(event) {
                channel.send("Hi!");
              }
            }

            function localicecandidate (event) {
              console.log("Local got new Ice Candidate: " + event.candidate);
              remote.addIceCandidate(new RTCIceCandidate(event.candidate));
            }
            function remoteicecandidate (event) {
              console.log("Remote got new Ice Candidate: " + event);
              local.addIceCandidate(new RTCIceCandidate(event.candidate));
            }
          
          }); 
        })
      }
        
      catch (e) {
        console.log("Got Error" + e);
      }```

Answer 1

在调用 createOffer 之前您没有调用 createDataChannel，因此 SDP 不包含 m=lines。如果没有 m 线，ICE 就没有任何谈判余地。

将

let channel = local.createDataChannel("channel");

移至 createOffer 之前。