当我从服务中调用函数时，"this"是未定义的

问题描述

我在component page

this.timerSessionService.startTimer(this.finish.bind(this), this.onSynchronice);

好吧，它与this.finish一起使用时很好，但是当我从Service调用onSynchronice时，它仍然可以工作并转到我的component，问题出在我的component上，我尝试调用使用.this在我组件内部的函数，它说:

well, it works great with the this.finish, but when I call onSynchronice from my Service it still works and goes to my component the problem comes when on my component I try to call a function that is inside of my component using .this, it says:

这是因为在我的onSynchronice函数上我使用了.this，然后它说它不存在...我该如何解决?

this is because on my onSynchronice function I use .this and then it says it does not exist... how do I fix it?

onSynchronice(pew) {
  console.log(pew["pew"]); //Works perfect
  this.pew= pew; //Crashes because of .this
  this.anyfunction(pew); //It crashes and says the same, anyfunction() does not exist, even if it exists
}

推荐答案

您可以将onSynchronice定义为箭头函数:

You can define onSynchronice as an arrow function:

onSynchronice = (pew) => {
    console.log(pew["pew"]);
    this.pew= pew;
    this.anyfunction(pew);
}

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