摄像头关闭：按MDN文档来写

src/components/FaceRecognition/FaceRecognition.vue

@@ -71,6 +71,7 @@ export default {
           this.$refs.video.srcObject.getTracks().forEach(function(track) {
             track.stop();
           });
+          this.$refs.video.srcObject.srcObject = null;
         }
       } else {
         this.openCamera();
@@ -81,13 +82,14 @@ export default {
     this.openCamera();
   },
   beforeDestroy() {
+    clearTimeout(this.retrySnapTimeout);
+    clearTimeout(this.showSnapResultTimeout);
     if (this.$refs.video.srcObject) {
       this.$refs.video.srcObject.getTracks().forEach(function(track) {
         track.stop();
       });
+      this.$refs.video.srcObject.srcObject = null;
     }
-    clearTimeout(this.retrySnapTimeout);
-    clearTimeout(this.showSnapResultTimeout);
   },
   methods: {
     ...mapMutations(["toggleSnapNow", "decreaseSnapCount"]),

src/features/OnlineExam/CheckComputer.vue

@@ -822,13 +822,14 @@ export default {
     await this.openCamera();
   },
   beforeDestroy() {
+    clearInterval(this.getNowInterval);
+    clearTimeout(this.checkClockRateTimeout);
     if (this.$refs.video.srcObject) {
       this.$refs.video.srcObject.getTracks().forEach(function(track) {
         track.stop();
       });
+      this.$refs.video.srcObject.srcObject = null;
     }
-    clearInterval(this.getNowInterval);
-    clearTimeout(this.checkClockRateTimeout);
     closeWsWithoutReconnect();
   },
   methods: {