angular - 错误：Angular 2 中的 BehaviorSubject

Question

---

receiveMessage(){
 this.messaging.onMessage(function (payload) {
    console.log("Message received. ", payload);
      this.currentMessage.next(payload)
  });
}

---

TypeError：无法读取未定义的属性“下一个”

标签： angular

Answer 1

尝试使用如下箭头函数，

 this.messaging.onMessage((payload) => {
      console.log('Message received. ', payload);
      this.currentMessage.next(payload);
 });

并确保您已导入，

import {BehaviorSubject} from 'rxjs/BehaviorSubject';