phone的websocket添加错误日志打印

src/app/services/websocket-phone.service.ts

@@ -30,7 +30,11 @@ export class WebsocketPhoneService {
       //socket 获取后端传递到前端的信息
       console.log('onmessage')
       if (event.data && event.data.length > 1) {
-        that.subject.next(JSON.parse(event.data));
+        try {
+          that.subject.next(JSON.parse(event.data));
+        } catch (error) {
+          console.error('返回的值是'+event.data+'，无法解析');
+        }
       }
     }